Gyan, who spent a season in the Premier League with Sunderland in 2009-10, already earns approximately £160,000-a-week with current side Al Ain.
"I want to really thank the entire Al Ain club and its fans for the support they have given me in my time there," Gyan told Al Ain's official website.
"It is however time to embrace a new challenge and hopefully this new challenge will be as successful or even better than my time here at Al Ain."
Gyan looked delighted as he touched down at the Shanghai Pudong International Airport. The 29-year-old's new side is managed by former England manager Sven Goran-Eriksson.