PURPOSE: To provide an operation mechanism for a toggle type switch which always shows quick-break by retaining a closed condition of a contact device at the early stage of opening operation, and by opening/closing the contact device at high pseed when the engagement of a latch means is released.

CONSTITUTION: An operation mecanism of a toggle type switch comprises a contact device A having a disconnection spring 24 for a moving contact device E, an opening/closing operation part F having arms 39, 40 provided with a roller 41 and a handle, moving arms 44, 44', which are directly connected with the moving contact deivce, and which have latch receiving parts 44b, 44'b and cam surfaces 44a, 44'a, a toggle spring mechanism G and the like having an operation spring 31 and the like, a clutch means H by which the latch receiving part of the moving arm provided directly before the input position of the opening/closing operation part can be engaged, and a latch control means, which interlocks with the operation of the opening/closing operation part, and by which the engagement between the clutch means and the latch receiving part is released in the middle of an openning process. Current disconnection is thus surely carried out by this operation mechanism serving as a quick-break mechanism.