Abstract: We developes infrared ray position detecting device for shearer based on carrier modulation, designs the hardware circuit and detection program, analyzes the operation principle of the detecting device, and makes the industrial tests.The results show that the design of the detecting device is reasonable; the detecting device is easy and convenient installation, accurate detecting data, strong anti-interference ability, which is suitable for real-time detection relative position between shearer and hydraulic support in full mechanized working face.