Abstract: For measuring the internal unsaturated soil under rainfall infiltration migration characteristics of uniform flow,with the help of a transparent soil test technology to carry out the indoor model test.Using the pixel intensity of black and white reference points to correct the pixel intensity of free infiltration transparent soil. And establish the functional relationship between normalized pixel intensity and saturation to analyze the characteristics of unsaturated uniform infiltration of transparent soil under different boundary conditions. The results show that the saturation of unsaturated transparent soil can be characterized by pixel intensity, and the uniform infiltration process of unsaturated transparent soil can be simulated. The open system exhaust smoothly, the closed system infiltration process is hindered by gas, its saturation is about 0.8 times of the open system. The saturation front appears after the wet front reaches the boundary of the phreatic layer, and the saturation is slightly lower than that of the open system. Pore pressure increases gradually from 0kPa when wet front passes under ventilation condition, and from 0kPa when fluid permeates under Sealing condition. The infiltration rate and cumulative infiltration rate decrease with the increase of initial oil content and decrease with the decrease of oil transport intensity.