The invention provides a detection method and device of the operating state of an air conditioner and a server, and relates to the technical field of air conditioners. According to the method and thedevice, a state detection request is sent to the server by a client, so that the air conditioner is controlled to operate by the server, and then the operating state of the air conditioner is judged according to operating data which are fed back by the air conditioner and operating data of other air conditioners in an area in which the air conditioner is located; the detection process is simple and quick, and to-be-detected items are set in advance, so that the condition of missing detection cannot occur, and the time of installation personnel is saved.