A model of metal wear debris sensor for lubricating oil was presented based on the principle of electromagnetic induction,and the basic structure and detection circuit of metal abrasive sensor were designed.The ability of the sensor to detect the antimagnetic abrasive grains and ferromagnetic abrasive grains was tested on the sensor test bench,and the influence of voltage and temperature on the sensor was studied.The test results show that the sensor can accurately distinguish the iron abrasivegrains and copper abrasive grains in the lubricating oil.The minimum detection diameters of the iron and copper abrasive grains are 200 μm and 500 μm respectively.The output characteristic of the sensor is stable in the voltage range of 3 V to 5 V,and the effect of temperature on the sensor can be ignored accuracy and the measurement can meet the requirements in the temperature range of 20 ℃ to 60 ℃.