Abstract: The standing-up mechanism of a multifunction walking assistance robot is developed to help the patients with lower limb diseases to stand-up normally, and only one actuator is used for motion control. The normal people's standing-up kinematics of hip, knee, ankle joints are obtained by an information measurement system, which is composed of a joint angle measuring system, a metronome and the dSPACE semi-physical simulation platform. Based on that information, the kinematic simulation of normal people's standing-up is analyzed by SimMechanics. By immigrating the hip's motion, the motion of the end-effector of the standing-up mechanism is designed. In human experiment, volunteers can stand up from sitting with the help of the prototype of walking assistance robot.