A laser diode (LD) driving system was presented, which mainly contains high-stable temperature control circuit, high-stable current control circuit and protection circuit. Concrete circuit was given. The laser can work stably by simultaneously control the current and temperature precisely. The protection circuit can provide sufficient protection to LD during its working. Without it, LD can be easily damaged by false operation or other reasons. Experimental results show that the output wavelength of the LD under constant temperature (room temperature) drifts no more than 0.6 pm. When the environmental temperature changes from 10°C to 50°C, the drift is no more than 16 pm, which, accordingly, can be applied to circumstances that request for high stability of LD.