The role at Facebook is understood to be a newly created position. She will report to recently appointed Fergus O'Hare, head of Creative Shop, Asia-Pacific at Facebook and will continue to be based out of Singapore. O'Hare replaced Peter Riley in the role in June earlier this year.
Cheng has been with JWT for five years, including two as chief creative officer.
“I had a wonderful run in recent years," said Cheng in a statement. "I am now ready to take on new challenges and push my capabilities in a new and exciting domain."
Victor Ng, who has been recently named ECD for J. Walter Thompson Singapore, will assume creative leadership of the agency. Ng joined from Havas Worldwide where he was Southeast Asia CCO.
Cheng will stay on with the agency until her move to help the transition.