In order to reveal the firing mechanism of firearms, study the firing failure mechanism of firearms and improve the firing reliability, a simulation test device for firing system of firearms was designed. By changing the height of the drop hammer, different firing energy conditions can be provided for the test unit. Firing pin and cartridge case with primer are used as test objects to simulate the assembly relationship and actual working conditions of the firing system in firearms. The test results show that the test unit and the monitoring unit can test the output characteristic parameters of the primer, such as flame length, flame duration and pressure characteristic parameters, and realize the quantitative evaluation of the firing performance of firearms.