The invention relates to a prefabricated cabin base turnover tool, which comprises two end part revolving seats connected to two ends of a length direction of a prefabricated cabin base. Each end partrevolving seat comprises a connecting frame connected with the prefabricated cabin base and a support seat for supporting the corresponding connecting frame; each connecting frame is rotatably arranged on the corresponding support seat around a horizontal axis; and each support seat is provided with a force applying part for a lifting device to upwards apply a force so as to realize height adjustment of the support seat, or a liftable seat for adjusting the height of the support seat. When in use, the prefabricated cabin base is arranged on two connecting structures, the lifting devices liftthe support seats or the support seats are lifted to a certain height, the prefabricated cabin base is turned over along with the connecting structures, and a back face of the prefabricated cabin basecan be processed after turnover is completed. Compared with the prior art, the turnover operation of the prefabricated cabin base does not depend on a crane, the prefabricated cabin base can be turned over within a limited space, the processing speed of the prefabricated cabin base is improved, and the working efficiency and the safety are improved.