Tao joined the agency in September 1993 as an account executive. Shenan Chuang, CEO of Ogilvy & Mather Greater China, confirmed Tao's departure.
"Since our earliest days 20 years ago Raymond has contributed so much to building O&M Advertising into what it is today, and he has always exemplified what David Ogilvy meant when he described 'a gentleman with brains'," Chuang said.
To fill the position while O&M hunts for a new permanent leader, Chris Reitermann will temporarily serve as acting China president, in addition to his role as Asia-Pacific president.
Tao, 47, was promoted to his current national role in 2009 after overseeing the agency's Beijing accounts, such as Motorola and China Mobile.
His move closely follows the August departure of Angel Chen, another Ogilvy veteran.