The in-situ rapid coalbed methane content tester consists of an underground coal sample sealing and crushing system, an automatic desorption gas measurement system, and an intelligent data processing system. The underground coal sample sealing and crushing system utilizes a high-pressure-retaining tank as its carrier and relies on underground compressed air as its power source. Through a mechanical rotation device, it achieves on-site pulverization of coal samples, effectively resolving the issue of low methane content readings caused by gas leakage from sample containers. The automatic desorption gas measurement system employs a high-sensitivity, high-precision load cell to directly measure the weight loss during drainage. This data is converted into desorbed gas volume, eliminating manual reading errors and overcoming the accuracy limitations of gas flow sensors. The intelligent data processing system incorporates a high-precision coal seam gas content processing model. It analyzes collected gas desorption data to rapidly calculate coal seam gas content measurement results, instantly generates result reports, and displays them in real-time via a human-machine interface. Utilizing mobile terminals, the system also enables full-process video recording of testing procedures and on-site signatures by test personnel, meeting traceability requirements for test results.