This paper deals with modeling and analysis for the landing motion of a human-body model. First, the dynamic model of a floating human body and the impact model are derived and the external impulse exerted on the ground as well as the internal impulse experienced at the joints of the human body model are investigated. Second, a motion planning algorithm exploiting the kinematic redundancy is suggested to ensure stability in terms of ZMP stability condition during a series of landing phases. Four phases of landing motion are investigated. In simulation, the external and internal impulses experienced at the human joints and the ZMP history resulting from the motion planning are analyzed for two different configurations. A desired landing posture is suggested by comparison of the simulation results.