In order to improve the detection accuracy of micro inductance sensor chip, the relationship between the velocity of ferromagnetic particles and the magnitude of inductance signal was studied.A micro inductance sensor chip was developed and a detection system was established.The relationship between the velocity of ferromagnetic particles and the amplitude of the induced pulse signal generated by the particles was studied experimentally.The experimental results show that for the same iron particles, the amplitude of the induction pulse signal is negatively correlated with the speed passing through the chip.The study results provide reference for improving the detection accuracy and sensitivity of micro-inductance sensor chips.