Scheduled for an Earth-to-Mars launch opportunity in 2020, the China’s Mars probe will arrive on Mars in 2021 with the primary objective of injecting an orbiter and placing a lander and a rover on the surface of the Red Planet. For China’s 2020 Mars exploration mission to achieve success, many key technologies must be realized. In this paper, China’s 2020 Mars mission and the spacecraft architecture are first introduced. Then, the preliminary launch opportunity, Earth–Mars transfer, Mars capture, and mission orbits are described. Finally, the main navigation schemes are summarized.