Hybrid trajectory is one of the most important trajectory types for manned lunar landing mission. Using the componential characteristic of hybrid trajectory, a hybrid trajectory calculation method based on free return trajectory was proposed under double two-body model. Then, the major characteristics of hybrid trajectory were analyzed, such as energy requirement and time of flight. A little modification was made when calculating the ephemeris of the Moon, in which the Moon motion around Earth was considered as noncircular orbit instead of circular orbit. Finally, a design example was presented while the results of the simulation validate the method proposed.