Fifth-ranked Jankovic, the Serbian former world No. 1, advanced first by taking a quarterfinal match-up against Japan's Misaki Doi 6-3, 6-4, then continuing with a 6-7 (2-7), 7-5, 6-1 semifinal victory over Zheng Jie of China.
Her opponent, the United States' Oudin, reached the title match with a 6-4, 5-7, 7-5 quarterfinal victory over fellow American Irina Falconi and a 6-4, 3-6, 6-2 win in the semis against Russian Ekaterina Makarova.
Two days of rain delays necessitated the playing of both the quarters and semifinals Sunday, with the championship match set for Monday.
Jankovic will be seeking her first title since 2010 while Oudin is making her first-ever finals appearance in the grass-court Wimbledon tune-up.