In the hydraulic system, metal abrasive particles are the important indicator which effects the normal operation of the hydraulic system. In this study, one kind of chip with a circular flow channel is introduced. The microfluidic oil metal particle counter is based on the principle of inductance and capacitance, which causes magnetic flux change or dielectric when abrasive particles, bubbles and water droplets in the hydraulic oil flow through the space micro solenoid. Inductive detection method is utilized to detect 30 μm iron particle and 110 μm copper particle using a 27inch coil at an excitation frequency of 2 MHz. The 100 μm water droplets and 180 μm bubbles are detected by a capacitance detection method at an excitation frequency of 13 MHz. Experimental results show that the detection accuracy of iron is obviously improved. The signaltonoise ratio based on the original detection accuracy is improved. Meanwhile, the diameter of the flow channel is increased, the flux of the detected hydraulic oil is increased, and the efficiency of detecting the particles is enhanced. This improved chip has good practical application value and broad development prospects.