A switching-on and switching-off integrated mechanism of an outdoor high-voltage vacuum circuit breaker comprises a frame composed of a left clamping plate, a right clamping plate and a fixed column, the fixed column is arranged between the left clamping plate and the right clamping plate, a switching-on system, a switching-off system, an interlocking device, a signal output device, an electrical control element, an output connecting lever and a drive main shaft are arranged on the frame, the drive main shaft is arranged between the left clamping plate and the right clamping plate in parallel, the output connecting lever is composed of a connecting arm, a first interlocking arm and a second interlocking arm, and the connecting arm, the first interlocking arm and the second interlocking arm are arranged to be of a Y-shaped structure. The overall dual-clamping-plate structural design is adopted, switching-on and switching-off accuracy is improved through guide limiting holes in the left clamping plate and the right clamping plate, the cam and drive main shaft integrated technique design of varying accelerated motion rules is adopted, and switching-on spring and switching-ff spring assembling, single conversion and output and a buffer are integrated on the mechanism. Assembling quality is guaranteed, the assembling process is simplified, the situation that elements are damaged by the error operation of non-technical personnel is avoided, and detection work is greatly facilitated.