Aimed at the shortcomings of the commonly used method for the monitoring of the ferromagnetic particles in the lubricating oil，magnetic force measurement method was presented to monitor the total amount of ferromagnetic particles in the oil.The measuring principle of this method was analyzed，and the corresponding experimental apparatus was designed.The experimental result shows that the amount of ferromagnetic particles and the magnetic force produced by the ferromagnetic particles in the oil has good linear relationship under the strong magnetic field，It is feasible to monitor the amount of magnetic particle in the oil by magnetic force measurement method.The magnetic measurement method is a fast and effective method for the monitoring of iron magnetic particles in oil，it is very sensitive to the content of the ferromagnetic particles in the oil，and is not affected by the size of the ferromagnetic particles.