The utility model relates to a rock-soil test technology, and aims to provide a supergravity rainy strong slope rainfall simulation device. The device comprises a model box installed on a supergravitycentrifuge, a slope model and a rainfall system are arranged in the model box, and the rainfall system comprises a plurality of sets of nozzles arranged relative to the surface of the slope model; each group of nozzles consists of an air atomizing nozzle, a circular atomizing nozzle and a square atomizing nozzle, and the three nozzles are arranged in a manner that the symmetric centers of the three nozzles form a triangle; each nozzle is connected to three water delivery branch pipes according to the type of the nozzle, and an electric control valve is arranged on each water delivery branch pipe. According to the utility model, the problem that the rainfall intensity cannot be adjusted in a large range in the existing supergravity test is solved, and the requirements of the supergravity test on the particle size of raindrops, the rainfall uniformity and the like are considered.