Abstract: The scholars at home and abroad have carried out a large number of failure tests on defect-free slopes under rainfall conditions, but most of the slopes in nature are defective. In this study, the centrifugal model tests on the defective and homogeneous slopes are carried out under rainfall conditions. The wetting peaks of the slopes are expressed, the changes displacement field of the slopes are measured, and the deformation and instability characteristics of the homogeneous and defective slopes are analyzed. The test results show that the velocity of rainwater infiltration increases due to the defects under rainfall conditions, and the defective slope and the homogeneous slope exhibit different wetting peaks, and the deformation of the defective slope is more severe. The defects change the depth of the slip surface and the shape of the defects, so that the slope has a composite failure mode of scouring failure and sliding failure, while the homogeneous slope only has erosion failure. Under rainfall conditions, the defect changes the strain distribution in the soil, accelerates the soil sliding near the defect, and aggravates the slope failure.