Based on the principle of microfluidic inductive detection, this paper designs a micro viscosity measurement sensor for marine lubricating oil. The motion law of metal particles in the microchannel is studied by numerical simulation and experimental verification. The effects of parameters such as oil viscosity, oil density, particle diameter, particle density, and particle position on particle velocity are studied respectively. When the particles move at the bottom of the microchannel, as the particle diameter increases, the particle velocity first increases and then decreases. Among them, when the particle diameter is less than 600µm, the particle diameter is linearly proportional to the particle velocity at the same viscosity. The viscosity measurement experimental results at different temperatures are consistent with the simulation results. This study provides new ideas for the motion law of metal particles in microchannels, and also provides a new method for measuring the viscosity of marine lubricating oil, which avoids the occurrence of a major malignant accident.