The invention discloses an operation mechanism of a low-voltage circuit breaker, which comprises a first connecting rod, a second connecting rod, a first hinged shaft, a second hinged shaft and a third hinged shaft; the first connecting rod is connected with one end of the second connecting rod through the second hinged shaft; the other end of the first connecting rod is connected with a handle hinge through the first hinged shaft; the other end of the second connecting rod is connected with a hinge at the other end of a rocker through the third hinged shaft; a restraint groove formed on a trip restrains the second hinged shaft 21 to only slide in the groove; one end of an energy storage spring is connected with a frame or an element fixedly connected with the frame, while the other end is connected with the third hinged shaft; and the first hinged shaft can transit between a first stop position and a second stop position to and fro, so that the operation mechanism is converted between a first stable state corresponding to the first stop position and a second stable state corresponding to the second stop position. The operation mechanism has compact and reasonable structure, smallvolume, strong function, good performance, easy production and manufacture and low cost.