A miniature circuit breaker with an automatic opening/closing function, comprising a circuit breaker body and an automatic opening/closing driving mechanism, the circuit breaker body comprising one to four circuit breakers each comprising a plastic housing, an opening/closing handle and a manipulation mechanism, a spindle hole being formed at the rotation center of each opening/closing handle, wherein: the automatic opening/closing driving mechanism comprises a case, a driving motor provided with a driving turbine, a linkage turbine, a linkage gear, an output spindle and a release linkage member, one end of the output spindle extending out of the case and inserted into the spindle hole of each opening/closing handle; the manipulation mechanism of each circuit breaker comprises an opening release linkage rod and an opening release linkage groove; turbine teeth fitted with the driving turbine are provided on the whole peripheral wall of the turbine driven portion; the driving motor drives the linkage turbine to do reciprocating rotation via the driving turbine, the linkage turbine drives the linkage gear and the output spindle to do synchronous rotation via the driving teeth, characterized in that; the other end of the output spindle is fixedly disposed at the center of the linkage gear, a linkage hole is formed on the wall of the plastic housing, and the opening release linkage rod of a circuit breaker abutting the automatic opening/closing driving mechanism extends into the case of the automatic opening/closing mechanism, the linkage turbine is integrally and concentrically provided with a turbine driven portion a gear driving portion and a cam linkage portion successively along its rotation central axis, a reset groove, a recess, a transition portion and a boss are successively provided on the periphery of the cam linkage portion; and a plurality of driving teeth fitted with the linkage gear are provided on part of the peripheral wall of the gear driving portion, a rotation central hole, a transmission rod portion and a lever portion are provided on the release linkage member, the transmission rod portion being used for abutting against the peripheral wall of the cam linkage portion of the linkage turbine, a reset notch being provided on the transmission portion, and further characterized in that the linkage turbine drives the release linkage member to do reciprocating rotation within a preset angle via the cam linkage portion so that the lever portion of the release linkage member prods the opening release linkage rod to perform a rapid opening action. the automatic opening/closing driving mechanism comprises a case, a driving motor provided with a driving turbine, a linkage turbine, a linkage gear, an output spindle and a release linkage member, one end of the output spindle extending out of the case and inserted into the spindle hole of each opening/closing handle; the manipulation mechanism of each circuit breaker comprises an opening release linkage rod and an opening release linkage groove; turbine teeth fitted with the driving turbine are provided on the whole peripheral wall of the turbine driven portion; the driving motor drives the linkage turbine to do reciprocating rotation via the driving turbine, the linkage turbine drives the linkage gear and the output spindle to do synchronous rotation via the driving teeth, characterized in that; the other end of the output spindle is fixedly disposed at the center of the linkage gear, a linkage hole is formed on the wall of the plastic housing, and the opening release linkage rod of a circuit breaker abutting the automatic opening/closing driving mechanism extends into the case of the automatic opening/closing mechanism, the linkage turbine is integrally and concentrically provided with a turbine driven portion a gear driving portion and a cam linkage portion successively along its rotation central axis, a reset groove, a recess, a transition portion and a boss are successively provided on the periphery of the cam linkage portion; and a plurality of driving teeth fitted with the linkage gear are provided on part of the peripheral wall of the gear driving portion, a rotation central hole, a transmission rod portion and a lever portion are provided on the release linkage member, the transmission rod portion being used for abutting against the peripheral wall of the cam linkage portion of the linkage turbine, a reset notch being provided on the transmission portion, and further characterized in that the linkage turbine drives the release linkage member to do reciprocating rotation within a preset angle via the cam linkage portion so that the lever portion of the release linkage member prods the opening release linkage rod to perform a rapid opening action.