V-type electro-thermal actuator is widely used in MEMS system because of its simple structure,large execution force and linear displacement. The thermoelectric effect is used to discuss the V-beam electro-thermal actuator, the theoretical analysis values of temperature distribution, maximum displacement and step response time are obtained, and the simulation results are verified by ANSYS. The result shows that the simulation results are consistent with the theoretical results. And the influence of the geometric parameters on the performance of the device is researched.