The time-optimal positioning control of a material transfer manipulators are analyzed in consideration of base oscillation. The second Lagrange method is used to establish the dynamic equation of the system, and a time-optimal controller based on implicit Lyapunov function is designed. Combined with the time-optimal stability lemma, Lyapunov theory is used to prove that the proposed control algorithm makes the positioning error converge to the origin in the finite time. The controller gain is continuous time-varying PD control. When the system state variable gradually approaches zero, the controller gain, as a differentiable function of the system state variable, gradually approaches infinity. The simulation results show that the controller can overcome the influence of base oscillation, and make the material transfer manipulators move to the specified position quickly with the time-optimal characteristics and anti-interference ability.