The disclosure describes an air circuit breaker comprising a compression coil (31); a first spring holder (302) to compress the compression coil in the axial direction thereof; and a second spring holder (301) which is subjected to the compression force of the compression coil, the first spring holder (302) being constructed in such a manner that it is formed of a plate material in a rectangular shape, a pair of projected pieces (316, 317) are provided on both sides of the plate material, and a pin (315) is held to pass between the pair of projected pieces in the direction of thickness of the plate so as to be able to support one end of the energy accumulating spring (31) at four points with the pair of projected pieces (316, 317) and the pin (315) in a compressible manner. After compression of said energy accumulating spring by pressure application thereto, its pressure application is released to stretch the energy accumulating spring so as to close a pair of contact points through the first and second spring holders (301, 302).