To provide a circuit breaker which has reliability and is reduced in size.

A circuit breaker includes: a first contact point at which switching between an open circuit state and a closed circuit state is performed; a second contact point at which switching between an open circuit state and a ground state is performed; an operation lever; and a rotary member which is rotated at a prescribed angle in accordance with operation of an operation lever. Furthermore, the circuit breaker includes: a first cam which opens and closes the first contact point which is rotated interlocked with rotation in one direction of the rotary member; and a second cam which opens and closes the second contact point which is rotated interlocked with rotation in the other direction of the rotary member.