The French top seed prevailed in two hours 41 minutes against the in-form Serbian to set up a meeting with second seed Svetlana Kuznetsova, who thrashed a weary Peng Shuai 6-0, 6-2 to end local hopes of a first homegrown champion.
"It was a really tough game. I'm really happy to go through, she played quite well," Mauresmo said.
"I will give all I have tomorrow night but I'm expecting another tough match."
Mauresmo, who ended a six-year losing streak against Lindsay Davenport in the quarter-finals, looked to be set for an easy passage to her sixth final of the year when she won the first set with ease.
Jankovic, though, has stopped a string of top-10 players in recent months and upped her game to break Mauresmo twice and claim the second set.
The third set was a topsy-turvy affair with each player losing their serve four times before the Australian Open and Wimbledon champion edged the sixth seed 7-3 in the tiebreak when Jankovic returned long.
"I broke her so many times I'm really disappointed, I hope I have another chance," said Jankovic.
Russian Kuznetsova won the toss and pretty much everything else in the earlier semi-final, dispensing with her 20-year-old opponent in just 51 minutes on a roasting Centre Court at the Beijing Tennis Centre.
"I played really smart," the 21-year-old Russian told reporters. "Shuai's a tough player but she was a little tired after yesterday."
Peng, her country's first semi-finalist at the China Open, said a combination of a recent operation on her leg and a two-and-a-half-hour quarter-final against Japan's Ai Sugiyama on Friday had left her unable to cope with her fifth-ranked opponent.
"I was very tired and afraid that I'd aggravate my injury so I didn't push myself to get every ball," said the 60th-ranked Peng.
Saturday's win was the seventh in a row for Kuznetsova, who won her second title of the year in Bali last week, and she was confident about meeting Mauresmo in the final.
"I'm looking forward to it," she said. "In our six meetings, I've lost four but won the last two. It's always motivating to play the world number one and I've got nothing to lose."
(Writing by Nick Mulvenney)
