The union, in a statement, said the vote was 65 percent in favor of the agreement among production workers. Among skilled trades workers who voted, 63 percent approved the deal, the UAW said.
The union reached a tentative agreement with GM on Sept. 16.
GM is the first of Detroit's three automakers to negotiate a settlement with the union. The UAW is now engaged in final talks to secure a labor accord with Ford Motor Co. The union's contract with Chrysler has been extended through Oct. 19.
GM CEO Dan Akerson and CFO Dan Ammann plan to brief financial analysts on terms of the deal at 2 p.m. ET today.
Under the pact, GM's 48,000 hourly workers have traded the promise of generous pay and benefits for job security and compensation gains that are more closely tied to the automaker's health, profitability and quality advances