Identification of laser menaces is an important aspect in laser warning and data disposing. The identifying method has direct effect on its veracity. Based on the fact that technique parameters of laser signal have some fuzzy characters in presenting menaces ,a method of identifying laser menaces based on fuzzy decision is presented. The fuzzication mathematical models of laser technique parameters such as laser energy, wavelength,repeat frequency, and fuzzy decision rules library of identifying laser menaces are built, which are set up by using fuzzy decision theory. Professional system of fuzzy decision is designed. Using different kinds of sensors in the laser warning system, parameters such as laser orientation, wavelength,repeat frequency, and characteristic of pulse are acquired. In virtue of the professional system of fuzzy decision, the type of the laser menaces is identified. Simulation result shows that the method can exactly identify the laser menaces , offer references for the study on the other data fusion of and has some practical value. The method can laser warning.