A detection algorithm for an infrared proximity sensor of a touch screen mobile phone is provided. The working principle is that, during the call, the detection algorithm detects the magnitude of the energy received by the infrared proximity sensor in real time, judges the proximity action or departure action according to the change trend, and adjusts the proximity and departure threshold values in real time to control the mobile phone screen to turn off and on. Said algorithm can avoid influences of the component consistency, structural consistency and other outside interference factors of the mobile phone on the infrared proximity detection, and solve the problem of malfunction due to aging of the IR-LED infrared emitter tube and clearance change caused by dropping of the mobile phone. The algorithm is widely applicable.