A management system, a smart meter, a server, an operation method and a management method are provided. The management system includes a remote server and at least one smart meter. The smart meter is coupled to the remote server via a communication network. The smart meter measures electrical energy of at least one power line to obtain at least one batch of electricity data. The smart meter detects whether the loading event occurs. If the loading event occurs, the smart meter performs data compression on the electricity data obtained during an event period corresponding to the loading event to obtain compressed data, and uploads the compressed data to the remote server. The remote server performs data decompression on the compressed data to obtain decompressed data. The remote server performs load identification according to the decompressed data.