exhibit23

We hereby consent to the incorporation by reference in the Registration Statements on Form S-8 (No.’s 333-34272, 333-34270, 333-82680, 333-123692 and 333-170810) of Cabot Microelectronics Corporation of our report dated November 22, 2011, relating to the financial statements, financial statement schedule, and the effectiveness of internal control over financial reporting, which appears in this Form 10-K.