In order to meet the requirements of response uniformity and rate of finished products in infrared detector manufacturing, studying and testing, a new test system of response for infrared detector is designed based on semiconductor modulated laser, which replaces blackbody radiation source. This system controls two-dimension scan workbench through computer, which accomplishes the data acquisition of detector. And the system uses the technology of VB call MATLAB realizing graphic model output, which reflects the response of detector clearly. The test process is completed automatically and the test precision reaches 0.001 2 V. The system provides an advanced method and test platform for studying and testing infrared detector automatically.