1. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCCOUNTING POLICIES (Policies)	9 Months Ended
Feb. 28, 2018
Accounting Policies [Abstract]
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCCOUNTING POLICIES	1. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCCOUNTING POLICIES The accompanying financial information has been prepared by Aehr Test Systems, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission, or SEC. Certain information and footnote disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles in the United States (GAAP) have been condensed or omitted pursuant to such rules and regulations. In the opinion of management, the unaudited condensed consolidated financial statements for the interim periods presented have been prepared on a basis consistent with the May 31, 2017 audited consolidated financial statements and reflect all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of the condensed consolidated financial position and results of operations as of and for such periods indicated. These unaudited condensed consolidated financial statements and notes thereto should be read in conjunction with the consolidated financial statements and notes thereto included in the Company's Annual Report on Form 10-K for the fiscal year ended May 31, 2017. Results for the interim periods presented herein are not necessarily indicative of results which may be reported for any other interim period or for the entire fiscal year.
PRINCIPLES OF CONSOLIDATION	PRINCIPLES OF CONSOLIDATION. The condensed consolidated financial statements include the accounts of Aehr Test Systems and its subsidiaries (collectively, the "Company"). All significant intercompany balances have been eliminated in consolidation. For the Company’s majority owned subsidiary, Aehr Test Systems Japan K.K., the noncontrolling interest of the portion the Company does not own was reflected on the Condensed Consolidated Balance Sheets in Shareholders’ Equity and in the Condensed Consolidated Statements of Operations.
ACCOUNTING ESTIMATES	ACCOUNTING ESTIMATES. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Estimates are used to account for sales and revenue allowances, the allowance for doubtful accounts, inventory valuations, income taxes, stock-based compensation expenses, and product warranties, among others. The Company bases its estimates on historical experience and on various other assumptions that it believes to be reasonable under the circumstances. Actual results could differ materially from those estimates.
REVENUE RECOGNITION	REVENUE RECOGNITION. The Company recognizes revenue upon the shipment of products or the performance of services when: (1) persuasive evidence of the arrangement exists; (2) goods or services have been delivered; (3) the price is fixed or determinable; and (4) collectibility is reasonably assured. When a sales agreement involves multiple deliverables, such as extended support provisions, training to be supplied after delivery of the systems, and test programs specific to customers’ routine applications, the multiple deliverables are evaluated to determine the unit of accounting. Judgment is required to properly identify the accounting units of multiple element transactions and the manner in which revenue is allocated among the accounting units. Judgments made, or changes to judgments made, may significantly affect the timing or amount of revenue recognition. Revenue related to the multiple elements is allocated to each unit of accounting using the relative selling price hierarchy. Consistent with accounting guidance, the selling price is based upon vendor specific objective evidence (VSOE). If VSOE is not available, third party evidence (TPE) is used to establish the selling price. In the absence of VSOE or TPE, estimated selling price is used. During the first quarter of fiscal 2013, the Company entered into an agreement with a customer to develop a next generation system, and the Company shipped the first system in July 2016. The project identifies multiple milestones with values assigned to each. The consideration earned upon achieving the milestone is required to meet the following conditions prior to recognition: (i) the value is commensurate with the vendor’s performance to meet the milestone, (ii) it relates solely to past performance, (iii) and it is reasonable relative to all of the deliverables and payment terms within the arrangement. Revenue is recognized for the milestone upon acceptance by the customer. The Company recognizes revenue in certain circumstances before physical delivery has occurred. In these arrangements, among other things, risk of ownership has passed to the customer, the customer has made a written fixed commitment to purchase the products, the customer has requested the products be held for future delivery as scheduled and designated by them, and no additional performance obligations exist by the Company. For these transactions, the products are segregated from inventory and normal billing and credit terms granted. Sales tax collected from customers is not included in net sales but rather recorded as a liability due to the respective taxing authorities. Provisions for the estimated future cost of warranty and installation are recorded at the time the products are shipped. Royalty-based revenue related to licensing income from performance test boards and burn-in boards is recognized upon the earlier of the receipt by the Company of the licensee’s report related to its usage of the licensed intellectual property or upon payment by the licensee. The Company’s terms of sales with distributors are generally FOB shipping point with payment due within 60 days. All products go through in-house testing and verification of specifications before shipment. Apart from warranty reserves, credits issued have not been material as a percentage of net sales. The Company’s distributors do not generally carry inventories of the Company’s products. Instead, the distributors place orders with the Company at or about the time they receive orders from their customers. The Company’s shipment terms to our distributors do not provide for credits or rights of return. Because the Company’s distributors do not generally carry inventories of our products, they do not have rights to price protection or to return products. At the time the Company ships products to the distributors, the price is fixed. Subsequent to the issuance of the invoice, there are no discounts or special terms. The Company does not give the buyer the right to return the product or to receive future price concessions. The Company’s arrangements do not include vendor consideration.
SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES. The Company’s significant accounting policies are disclosed in the Company’s Annual Report on Form 10-K for the year ended May 31, 2017. There have been no significant changes in our significant accounting policies during the nine months ended February 28, 2018.

1. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCCOUNTING POLICIES (Policies)

9 Months Ended

Feb. 28, 2018

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCCOUNTING POLICIES

1. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCCOUNTING POLICIES

The accompanying financial information has been prepared by Aehr Test Systems, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission, or SEC. Certain information and footnote disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles in the United States (GAAP) have been condensed or omitted pursuant to such rules and regulations.

In the opinion of management, the unaudited condensed consolidated financial statements for the interim periods presented have been prepared on a basis consistent with the May 31, 2017 audited consolidated financial statements and reflect all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of the condensed consolidated financial position and results of operations as of and for such periods indicated. These unaudited condensed consolidated financial statements and notes thereto should be read in conjunction with the consolidated financial statements and notes thereto included in the Company's Annual Report on Form 10-K for the fiscal year ended May 31, 2017. Results for the interim periods presented herein are not necessarily indicative of results which may be reported for any other interim period or for the entire fiscal year.

PRINCIPLES OF CONSOLIDATION

PRINCIPLES OF CONSOLIDATION. The condensed consolidated financial statements include the accounts of Aehr Test Systems and its subsidiaries (collectively, the "Company"). All significant intercompany balances have been eliminated in consolidation. For the Company’s majority owned subsidiary, Aehr Test Systems Japan K.K., the noncontrolling interest of the portion the Company does not own was reflected on the Condensed Consolidated Balance Sheets in Shareholders’ Equity and in the Condensed Consolidated Statements of Operations.

ACCOUNTING ESTIMATES

ACCOUNTING ESTIMATES. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Estimates are used to account for sales and revenue allowances, the allowance for doubtful accounts, inventory valuations, income taxes, stock-based compensation expenses, and product warranties, among others. The Company bases its estimates on historical experience and on various other assumptions that it believes to be reasonable under the circumstances. Actual results could differ materially from those estimates.

REVENUE RECOGNITION

REVENUE RECOGNITION. The Company recognizes revenue upon the shipment of products or the performance of services when: (1) persuasive evidence of the arrangement exists; (2) goods or services have been delivered; (3) the price is fixed or determinable; and (4) collectibility is reasonably assured. When a sales agreement involves multiple deliverables, such as extended support provisions, training to be supplied after delivery of the systems, and test programs specific to customers’ routine applications, the multiple deliverables are evaluated to determine the unit of accounting. Judgment is required to properly identify the accounting units of multiple element transactions and the manner in which revenue is allocated among the accounting units. Judgments made, or changes to judgments made, may significantly affect the timing or amount of revenue recognition.

Revenue related to the multiple elements is allocated to each unit of accounting using the relative selling price hierarchy. Consistent with accounting guidance, the selling price is based upon vendor specific objective evidence (VSOE). If VSOE is not available, third party evidence (TPE) is used to establish the selling price. In the absence of VSOE or TPE, estimated selling price is used.

During the first quarter of fiscal 2013, the Company entered into an agreement with a customer to develop a next generation system, and the Company shipped the first system in July 2016. The project identifies multiple milestones with values assigned to each. The consideration earned upon achieving the milestone is required to meet the following conditions prior to recognition: (i) the value is commensurate with the vendor’s performance to meet the milestone, (ii) it relates solely to past performance, (iii) and it is reasonable relative to all of the deliverables and payment terms within the arrangement. Revenue is recognized for the milestone upon acceptance by the customer.

The Company recognizes revenue in certain circumstances before physical delivery has occurred. In these arrangements, among other things, risk of ownership has passed to the customer, the customer has made a written fixed commitment to purchase the products, the customer has requested the products be held for future delivery as scheduled and designated by them, and no additional performance obligations exist by the Company. For these transactions, the products are segregated from inventory and normal billing and credit terms granted.

Sales tax collected from customers is not included in net sales but rather recorded as a liability due to the respective taxing authorities. Provisions for the estimated future cost of warranty and installation are recorded at the time the products are shipped.

Royalty-based revenue related to licensing income from performance test boards and burn-in boards is recognized upon the earlier of the receipt by the Company of the licensee’s report related to its usage of the licensed intellectual property or upon payment by the licensee.

The Company’s terms of sales with distributors are generally FOB shipping point with payment due within 60 days. All products go through in-house testing and verification of specifications before shipment. Apart from warranty reserves, credits issued have not been material as a percentage of net sales. The Company’s distributors do not generally carry inventories of the Company’s products. Instead, the distributors place orders with the Company at or about the time they receive orders from their customers. The Company’s shipment terms to our distributors do not provide for credits or rights of return. Because the Company’s distributors do not generally carry inventories of our products, they do not have rights to price protection or to return products. At the time the Company ships products to the distributors, the price is fixed. Subsequent to the issuance of the invoice, there are no discounts or special terms. The Company does not give the buyer the right to return the product or to receive future price concessions. The Company’s arrangements do not include vendor consideration.

SIGNIFICANT ACCOUNTING POLICIES

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES. The Company’s significant accounting policies are disclosed in the Company’s Annual Report on Form 10-K for the year ended May 31, 2017. There have been no significant changes in our significant accounting policies during the nine months ended February 28, 2018.