The invention discloses an electricity consumption information acquisition device, system and method. The electricity consumption information acquisition device comprises an ammeter collector and an optical line terminal, wherein one end of the ammeter collector is used for being connected with an ammeter through a serial interface and acquiring first information sent by the ammeter, and the first information is packaging information based on a first communication protocol and comprises electricity consumption information acquired by the ammeter; the other end of the ammeter is connected with the optical line terminal through an optical fiber and used for forwarding the acquired first information to the optical line terminal; the optical line terminal is used for extracting electricity consumption information in the first information and converting the electricity consumption information into second information based on a second communication protocol, after that, the second information is sent to a master station system, and the second communication protocol is a protocol supported by the master station system. According to the electricity consumption information acquisition device, the protocol conversion process is executed by the optical line terminal, the cost is lowered, unified management is convenient, and the improvement cost is greatly cut.