In order to improve the safety, reliability and efficiency-cost ratio, according to working characteristics of certain type solid rocket motor inter-stage separation test, a release system based on electromagnetic principle and transistor drive was proposed. From the separation test principle, the designs for the electromagnetic device and the drive circuit of the release system were described in detail. The finite element model of the release system was established by Ansoft, the static and transient working processes were analyzed according to the force conditions and input requirements. The experimental results show that the separation time of the release system is 0.2~0.5 ms, which meets the requirements of separation test. The system can realize reliable pull-in and quick release functions.