The 29-year-old has joined from from Al Ain in the UAE on a two-year deal, after completing a routine medical.
Exact terms of the deal were not disclosed but local media have reported the former Sunderland striker will earn in excess of US$250,000 per week.
“I thank God for this special day, to my family, players and fans,” he said.
The former Sunderland FC of England striker will be officially unveiled next week.
During four years with Al Ain he scored 95 times in 83 appearances, and won three domestic league titles as well as being top scorer in the Arabian Gulf League three times.
Gyan’s arrival marks the latest big-money signing in China, where the top clubs have splashed out millions of dollars on high-profile players such as Demba Ba and Paulinho.