Based on the limitation of the laser imaging effect on an imaging system, a simulation method using full digital simulation technology is presented for the first time. At first, the laser imaging effect on the imaging system is analyzed and researched from three aspects such as laser effect on a detector, laser atmosphere transmission and laser effect image overlapping, and based on which, the simulation design of the laser effect is performed. The simulation of the effect is designed and a simulation system based on RTI bus is developed. And continuous dynamic simulation effect images are given under different conditions. At last, the application and the development of the simulation system are put forward.