The world number two from Serbia furthered his aim of finishing the year top of the ATP rankings with a simple straight-sets victory, maintaining his unbeaten record at the Beijing tournament that stretches back three years.
Top-seed Djokovic defeated the 29th-ranked Mayer of Germany 6-1, 6-4 with the help of seven aces.
The 25-year-old, second to Roger Federer in the rankings, has won the China Open on the two occasions he has entered — in 2009 and 2010 — and will aim to make it three out of three on Sunday.
“There are no secrets between us," Djokovic said of Tsonga whom he leads Tsonga 7-5 in head-to-heads. “He’s a very powerful player, big serve, big forehand, and if that works, he can win against anybody on any surface," he added.
Tsonga entered the final when Spain’s Feliciano Lopez retired during the second set of their match.