An alternating current contactor comprises a base and a magnetic yoke. The magnetic yoke is mounted on a bottom plate of the base. A magnetic yoke support for supporting and buffering the magnetic yoke is respectively provided at two sides of the magnetic yoke, wherein sidewalls at two sides of each magnetic yoke support, which are connected with the magnetic yoke are different in thickness. The magnetic yoke support of the alternating current contactor of the utility model has a simple structure due to the arrangement of an asymmetric eccentric structure. The up-down position of the magnetic yoke relative to the bottom plate of the base can be adjusted by changing an assembly direction of the magnetic yoke supports, thereby achieving the purpose of adjusting the total stroke of the product with high flexibility. When a dimension of a housing of a plastic part is abnormal, the magnetic yoke has a certain adjustment amount to ensure that the integral assembly of the product can be completed and the efficiency and reliability can be improved.