The rocket is expected to be launched at 07:38 GMT on Wednesday and to dock to the International Space Station (ISS) at 13:41 GMT, the same day. The crew will spend 12 days at the ISS.
Soyuz MS-20 will carry Japanese businessman Yusaku Maezawa, his assistant Yozo Hirano, who will make videos of Maezawa's actions for Youtube, and Russian cosmonaut Alexander Misurkin.
The Russian and the Japanese flags are placed on the spacecraft, which is also labeled with the logos of the Russian state space corporation Roscosmos, the Space Adventures company, and a personal logo of Maezawa.