The Serbian, who won this season's French Open in June, downed No. 7 seed Flavia Pennetta of Italy 6-4, 6-4.
"It was a tough match against a very good player," Ivanovic said. "We played at a very high level and it was one of the best matches I've played recently. I'm really happy with how I played against Flavia today."
Also Friday, second-seeded Vera Zvonareva of Russia overcame No. 8 seed Alize Cornet of France 7-5, 6-1; third-seeded Agnieszka Radwanska of Poland beat No. 5 seed Nadia Petrova of Russia 6-3, 6-2; while sixth-seeded Marion Bartoli of France was a 6-3, 5-7, 6-1 winner against unseeded Alona Bondarenko of Ukraine.
Saturday's semifinal matches will feature Ivanovic vs. Radwanska and Bartoli vs. Zvonareva.
The eventual champion will collect $95,500 for winning Sunday's title match.