The asymmetry of a-cut Nd∶YVO4 leads to asymmetrical laser output from laser diode (LD) end-pumped Nd∶YVO4 solid state laser, which differs from Nd∶YAG laser. The finite element was applied to analyze the thermal effect of LD end-pumped a-cut Nd∶YVO4 crystal, including temperature distribution, internal stress and its deformation. The results indicate that the thermal lens of end-pumped a-cut Nd∶YVO4 crystal takes the ellipsoidal distribution. The method of balancing the asymmetry of thermal lens was put forward by the way of structure and pumping, and experimentally proved feasible.