The invention provides a positioning method and device for a pseudo base station, and relates to the technical field of communication safety. The positioning method for the pseudo base station comprises the following steps: periodically acquiring signaling bill data of a plurality of cells; acquiring cells with abnormal location update according to the signaling bill data of the plurality of cells within the same statistical cycle; performing a clustering treatment on the cells with abnormal location update, and obtaining a plurality of cell clusters; and determining the position of the pseudo base station of each cell cluster according to the positions of the plurality of cells in each cell cluster and the location update abnormal condition. The positioning method obtains the cells with abnormal location update by analyzing the signaling bill data of the plurality of cells, clusters the cells affected by the same pseudo base station, and quickly positions the pseudo base station; on one hand, the quick positioning of the pseudo base station can be realized in terms of time; on the other hand, the positioning precision and accuracy can be improved in terms of space; therefore, the search range of capture work is reduced, the capture efficiency of the pseudo base station is improved, and a lot of manpower and financial resources are saved.