Abstract: The utility model discloses an alternating current contactor, including a foundation-support and a pedestal. A yoke iron on which mounts a coil unit is set inside the said foundation-support, and an armature iron and a contact unit are set in the said pedestal. The characteristics are that one side of the said foundation-support is open, and the coil unit and the yoke iron are constituted into a whole via a supporting board and buffer springs, and then it is fixed on the convex face of pulling part of the said foundation-support. A baffle plate with openings is on the top of the foundation-support, and a repelling force spring is installed between the baffle plate on the top of the foundation support and the armature iron. The coil unit can be easily inserted into or pulled out from the opening of the foundation-support, so that either repairing or replacing the coil unit become rather convenient.