EXHIBIT 23

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in the Registration Statements on Form S-8 (No. 333-130001, No. 333-123778, No. 333-75531, No. 333-57006, No. 333-57008, No. 333-57010, No. 333-57012) of Varian Medical Systems, Inc. of our report dated December 9, 2005, relating to the financial statements and the financial statement schedule, which appears in this Form 10-K.

/s/ PRICEWATERHOUSECOOPERS LLP

San Jose, California

December 12, 2005