The invention belongs to the technical field of aerospace medicine and exercise rehabilitation, in particular, relates to an acceleration generator. A reciprocating motion acceleration generator is characterized by comprising a motor (1), a turntable (2), a connecting rod (3), a pedal (4) and a fixed rod (5). The reciprocating motion acceleration generator uses the connecting rod connected with the turntable for driving the pedal to generate vertical motion; in the process of the motor driving the turntable to perform circular motion, the component of angle acceleration in one point in the z-axle direction presents a sine curve, so that the reciprocating motion in the z-axle direction can be generated; the magnitude of the acceleration in the z axle is related to the rotating period t and radius r of the turntable driven by the motor; the period t and the radius r can be adjusted through adjusting the rotating speed of the motor and the position of the fixed point; and the reciprocating motion acceleration generator has the advantages of low space requirement, low energy consumption, smoothness, mildness and no adverse reaction in use.