Vacuum circuit breaker

The invention relates to a vacuum circuit breaker. The vacuum circuit breaker of the invention includes a shell with a cavity arranged therein, a fixed contact, a moving contact, a switching moving contact, an operation portion, a telescopic pin and a pushing rod; a partition plate is arranged in the shell; the partition plate divides the cavity into an upper cavity and a lower cavity; the fixed contact is arranged at the top of the upper cavity; the moving contact is arranged below the fixed contact; the moving contact is fixed to the upper part of the pushing rod; the switch moving contact is arranged at the bottom of the lower cavity; the bottom of the pushing rod extends into the operation portion; two sides of the inner side wall of the lower cavity of the shell are symmetrically provided with a first trench and a second trench; the lower part of the pushing rod is provided with a slide way; and the telescopic pin is arranged in the slide way. According to the vacuum circuit breaker of the invention, whe