Transparent conductive films (TCFs) electrode electro-optic switch is an ideal switch device for high average power, which can achieve high thermal management efficiency by reasonable design. A model based on the schematic diagram of TCFs electro-optic switch is proposed. The switch′s time characteristics and thermal effects with average power loaded on the electro-optic are simulated by numerical modeling. The results show that the switch′s rise time can meet the requirements of the nominal time. The depolarization loss caused by temperature rise has small effect on the performance of the switch. The design of TCFs electro-optic switch for high average power can be applied to high average power laser system at high repitition-rate.