It will mark the first time Saudi Arabia sends women to compete in the Olympics, and the 2012 Olympics will be the first in history that every competing nation will send at least one female athlete, the IOC said.
"The IOC has been working very closely with the Saudi Arabian Olympic Committee, and I am pleased to see that our continued dialogue has come to fruition," IOC President Jacques Rogge said in a release.
Earlier, Brunei Darussalam and Qatar said they would also have female athletes competing for the first time in the Olympics.
Saudi Arabia will send Wodjan Ali Seraj Abdulrahim Shahrkhani, who will compete in judo, and Sarah Attar, who is running in an 800-meter race, the IOC said.
"A big inspiration for participating in the Olympic Games is being one of the first women for Saudi Arabia to be going," the 17-year-old Attar, who is training in San Diego, said in the release. "It's such a huge honor and I hope that it can really make some big strides for women over there to get more involved in sport."
Brunei Darussalam has entered Maziah Mahusin in athletics, while Qatar has entered Nada Arkaji in swimming; Noor Al-Malki in athletics; Aya Magdy in table tennis and Bahiya Al-Hamad in shooting.
Women are also to compete in boxing in London, marking the first time women will compete in every sport in the 116-year history of the modern Olympic Games, the IOC said.