A hand-operated operating mechanism of a circuit breaker belongs to the technical field of low-pressure switch accessories, and comprises a rack, an operating shaft which is mounted on the rack, a link mechanism which is moveably connected with the operating shaft, guided ways which are mutually fixed on the back of the rack in parallel, and slide blocks which are slidably matched with the guided ways. The utility model is characterized in that a gear with a connecting bar eccentric shaft is further provided, the center of the gear is pivoted on the back of the rack through a gear shaft, the connecting bar eccentric shaft is passed through an arc chute on the rack to be moveably connected with the link mechanism, and gear holes which are meshed with teeth on the gear are formed on the slide blocks. The utility model has the advantages that the needed external applied force is constant, a parallelogram structure is jointly formed by the operating shaft, a first connecting bar, a second connecting bar, and the gear shaft, thereby solving the problems of changing force moments, and meanwhile the limited space is fully used, the structure is compact, the slide blocks are rotated through the meshing of the gear and gear holes for eliminating the 'blocking' phenomenon, the reliable performance of the operating mechanism is guaranteed, and the mechanical service life is extended.