The embodiments of the disclosure provide a method and device for joining network processing of a sensor, network platform equipment and an Internet of things gateway. Wherein, the method includes that: a joining network request message used for requesting to perform joining network on the sensor is received, wherein the joining network request message contains Identity, ID, information of the sensor; a joining network state of the sensor is determined according to the ID information; and the determined joining network state is sent to an Internet of things gateway, wherein the joining network state is used for executing joining network processing on the sensor by the Internet of things gateway.