Djokovic has never lost in Beijing, winning the tournament all three times he has entered, beating Marin Cilic in the 2009 final and David Ferrer in 2010.
The first four games went with serve before Tsonga made a breakthrough in the fifth game, breaking Djokovic to love.
But Djokovic hit back immediately, and the next six games went with serve to force a tie-break, which he won 7-4 with the help of three unforced errors.
The Serb then claimed a break in the third game of the second set and served out to boost his hopes of finishing the year as he started it - as world No 1.
Djokovic admitted the first set could have gone either way.
He said on www.atpworldtour.com: "I think the first set was really even, and maybe a couple of points decided the winner there.
"I managed to hold my nerves in the end. When you're getting to the second set with the set advantage, mentally it is much more encouraging for you and then you try to play on that confidence run that you have.
"I made that early break in the second (and) I felt much more comfortable on the court."
The Serbian has now set his sights on finishing the year as world number one, having seen Roger Federer move back ahead of him.
He said: "That's the target. This will definitely help me in that race, but it's still quite open.
"There are still tournaments to come, big ones. Shanghai, obviously the first 1000 event that is next week.
"I want to try to get as far as I can in the tournament, obviously taking one match at a time as I always do."
Tsonga accepted that his opponent's class told in the end.
"I think it was a good match," the Frenchman said. "I missed maybe something in the middle of the first set.
"I was a break up, and I was playing well. But then he played solid. It was really difficult to control him. I just tried to play my game, to be aggressive, but against a player like this, for the moment, my level is not high enough, and it's not enough to beat him.
"I'm happy because I played good tennis here. It was a great tournament for me. I hope I will continue to improve like this and I will try another time to beat these guys next week."
Currently No 2, Djokovic closed the gap behind world rankings leader Roger Federer - who skipped Beijing - by 500 points.
Tsonga, meanwhile, remains firmly in contention to qualify for the year-ending ATP World Tour Finals in London.
If he does qualify for London Tsonga will hope he does not come up against Djokovic - in six matches now with the Serb he has yet to taste victory.
In the women's final, world number one Victoria Azarenka made light work of Maria Sharapova as she raced to a 6-3 6-1 win.
Azarenka broke three times in the first set and twice in the second as she claimed victory in one hour and 27 minutes.
Sharapova had her chances, particularly in the second set when she failed to convert any of her five break points, but her opponent punished her weak second serve.