Alexei Krasnov, the agency's director for manned missions, told the Japanese newspaper Asahi that Mr. Enomoto had passed a physical and was now starting a training program for a flight next fall.
An eight-day vacation at the International Space Station will cost the man $20 million.
U.S. billionaire Dennis Tito visited the ISS in 2001 as the first fare-paying "space tourist." South Africa's Mark Shuttleworth followed in 2002. American businessman and scientist Gregory Olsen winds up his stint on the ISS Tuesday.
Krasnov said money brought in by space tourism goes to support programs run by the agency.
He said the annual number of ISS tours for non-professionals will be increased to four in 2009, from today's two, and that ISS crews could be doubled thanks to the new Russian six-seater shuttle, the Klipper.