Some aircrafts are equipped with laser beacon system based on semiconductor laser module,which is used to emit a stable beam of certain power for capturing,identifying and tracking laser beacon with photoelectric system on the ground.Aiming at the high power stability requirement of the laser beacon system in a wide temperature range,two kinds of power control circuits of semiconductor laser module,closed loop and open loop,are designed respectively in this paper.The power control effects of the two control circuits at high and low temperature are tested by domestic and imported lasers.The results show that the control effect of constant voltage open loop circuit is better than that of constant power closed loop circuit.