A protection apparatus for air circuit breaker for preventing an erroneous operation caused by heat in the course of the air circuit breaker being operated is disclosed, wherein temperatures are detected using the detection signals of temperature sensors attached to various heat generating sources disposed at the air circuit breaker including power lines and contacts, and various constituent elements having a high likelihood of generating an erroneous operation when the temperature is high, and the detected temperatures are compared with prescribed reference temperatures, and as a result of the comparison, if the detected temperatures are higher than the prescribed reference temperatures, the air circuit breaker is determined to have a possibility of generating an erroneous operation, and if air circuit breaker is determined to have a possibility of generating an erroneous operation, the trip coil is driven to trip the air circuit breaker.
