Lisicki, a 2011 semifinalist at the All England Club, beat fourth-seeded Agnieszka Radwanska 6-4, 2-6, 9-7 Thursday on Centre Court, overpowering her opponent at the start and then hanging on at the end.
"I just fought with all my heart," Lisicki said. "I believed that I could still win no matter what the score was."
Bartoli took control of her match early and never let up in a quick 6-1, 6-2 victory over Kirsten Flipkens.
Bartoli also reached the Wimbledon final in 2007, losing to Venus Williams in straight sets.
Saturday's final will be the second at Wimbledon in the 45-year Open era between two women who have never won a Grand Slam title. Lisicki may have the edge in that match with a 3-1 record against Bartoli, including a quarterfinal win at Wimbledon in 2011 in their last meeting.
Lisicki, who beat defending champion Serena Williams in the fourth round, dictated play in the first set by winning 22 of her 30 points on serve and breaking once. But her serve deserted her after that.
Once the second set started, Radwanska came alive and Lisicki crumpled.
Lisicki lost all four of her service games, with the lowlight coming in the final game of the second set. Leading 30-0, Lisicki lost four straight points, including two double-faults.
In the third, Lisicki was again broken early but finally held to make it 3-1 and then broke to get back on serve.
Both players held serve until Lisicki got the deciding break in the 15th game when Radwanska hit a volley long.
A few minutes earlier, Radwanska had been two points from victory. The two were tied at 30-30 and later at deuce in the 12th game with Radwanska leading 6-5.
Lisicki said her big win over Serena Williams helped her Thursday.
"I thought, 'I've done it against Serena so you can do it today as well, just hang in there,'" Lisicki said. "It gave me so much confidence and I'm just so, so happy I was able to finish it."
Bartoli wasted little time in her match, dancing and grunting her way to victory over the 20th-seeded Belgian who was playing in her first major semifinal.
"I played great. I executed very well. I hit lobs, passing shots, winners, returns, everything worked out perfectly," said Bartoli, who won in 62 minutes. "When I fell on the grass after match point, it was just so emotional. I dreamed about that moment, about returning to the Wimbledon final."
Amelie Mauresmo, the 2006 Wimbledon champion who now coaches France's Fed Cup team, was in the stands for the early match and had plenty of praise for Bartoli.
"She just played a great match, definitely the best match of the tournament for her," Mauresmo said. "Marion put huge pressure on her right from the beginning, first of all returning very well, serving better, which she had to do today."
Bartoli was pumped from the start on Centre Court, mixing two-handed backhands and forehands with little hops between points, as she usually does.
In the first set, she faced only one break point, nearly putting Flipkens back on serve in the third game. But despite a double-fault and a backhand into the net to eventually get behind 30-40, Bartoli dug herself out of the hole and finished the game with the first of her five aces.
"I tried my slices. She didn't have any problem with that," Flipkens said. "I tried the dropshot. She got it. I played a passing, she came to the net. I tried a lob. I tried everything, actually."
Flipkens, who again took the court with her right knee taped, called for a trainer after being broken for the second straight time at the start of the second set. The trainer added tape to the knee while Bartoli sat in her chair sipping water.
Whatever she needed, it briefly worked. Flipkens, after the medical timeout, broke for the first and only time, making it 3-1. But a few minutes later Bartoli broke again and held to make it 5-1.
"First of all, I'm not going to use it as an excuse, that's for sure. I mean, Marion played an amazing, good match," Flipkens said. "But I fell in the first set. Straightaway I didn't feel anything, but I fell on my bad knee. At that moment I didn't feel it, but a couple of games later I started to feel a really sharp pain like I had four weeks ago."
Bartoli is now 2-1 in Grand Slam semifinals with both wins at Wimbledon. Six years ago, she beat another Belgian, top-seeded Justine Henin, in the semifinals. But then she ran into Venus Williams, who that year won the fourth of her five Wimbledon titles.
On Saturday, Bartoli will be on relatively equal footing against Lisicki.
"It's a good opportunity. She has experience at least," Mauresmo said of Bartoli. "Maybe it's going to help her for the final."
Copyright 2013 The Associated Press.