The Masai Mara is famed for the waves of wildebeest that migrate from Tanzania's Serengeti National Park north into the Mara once a year. Branson called the migration one of the top "wonders" in the world.
On the sidelines of a business conference in Nairobi on Thursday, Branson said his project "will help protect the migration routes by creating some reserves just around the Masai (Mara)."
Branson, who is to travel to the Masai Mara region Thursday and Friday, said he hoped the 15-tent luxury camp would be open in the next four to six months.
Branson has run a game reserve in South Africa for the last 20 years. He already helps fund the aid group Free the Children, which works in the Masai Mara region.