Disclosed is a smart home system based on a cloud platform. The system comprises: a mobile terminal for generating an instruction for controlling a home appliance and transmitting the instruction for controlling a home appliance to a cloud platform by means of a 3G, 4G or Wi-Fi network; the cloud platform for receiving the instruction for controlling a home appliance, processing the instruction for controlling a home appliance, selecting a valid instruction, and transmitting the valid instruction to a home local area network gateway; the home local area network gateway for receiving the valid instruction and transmitting the valid instruction to a corresponding home appliance; and the home appliance for receiving the valid instruction and executing a corresponding function according to the valid instruction. Also provided is a control method. By means of the smart home system based on a cloud platform and the control method provided in the invention, a home appliance can be remotely controlled, such that the problem of the home appliance wasting energy as a result of not being intelligent is alleviated. A simple and convenient remote home appliance control method is provided, thus facilitating the promotion and usage of a smart home device.