Document And Entity Information - shares	6 Months Ended
	Dec. 29, 2017	Feb. 02, 2018
Document Information [Line Items]
Entity Registrant Name	TWIN DISC INC
Entity Central Index Key	0000100378
Trading Symbol	twin
Current Fiscal Year End Date	--06-30
Entity Filer Category	Accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Entity Common Stock, Shares Outstanding (in shares)		11,584,892
Document Type	10-Q
Document Period End Date	Dec. 29, 2017
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q2
Amendment Flag	false