The invention relates to a detection method and device for a dedicated circuit breaker of a prepayment electric energy meter. The device consists of a high temperature test chamber, three voltage regulators, two current boosters, two current circuits and a voltage circuit. The two isolation current circuits are respectively connected to an inlet end and an outlet end of a current connection wire of the circuit breaker to form a loop. The voltage circuit is connected to inlet wire ends of the two current circuits, and a control wire of the circuit breaker is connected to a control wire connector of the inlet wire end of the circuit breaker. The detection method comprises the following steps: (1) wiring according to the detection requirements, and arranging the circuit breaker in a high and low temperature test chamber; (2) raising the temperature of the high and low temperature test chamber to 70 DEG C; (3) closing a control circuit switch, boosting the circuit breaker to rated voltage, boosting the current by the current boosters to rated current, measuring for 4 hours at a constant temperature, and observing whether the circuit breaker trips or not within the measurement time; and (4) disconnecting the control circuit switch and observing whether the circuit breaker trips or not. The method and the device are used for testing current and voltage trip properties simultaneously for the dedicated circuit breaker of the prepayment electric energy meter, and testing a prepayment control circuit function.