The dynamics characteristics of backward rotary transplanting mechanism with elliptical gears transmission are analyzed by using the method including differential equations of rigid compound motion and stepwise solving solution of dynamics equations group.Dynamics model of the mechanism is established

the software of mechanism aided analysis is developed and the relationships between rotary angle of planetary carrier and the force of several positions were obtained.The positions were chain

axle of central elliptical gear

axle of middle gear

axle of planetary gear

its dynamics characteristics are tested. The results show that the dynamics characteristics of this mechanism are better than the dynamics characteristics of the mechanism with crank-rocker.