This application presents a circuit, a battery management system, and an electric vehicle. The circuit includes: a first current collection module, a second current collection module and a calculation module. The first current collection module and the second current collection module are respectively connected in series with a main circuit and a control circuit of the battery management system. The calculation module calculates a state of charge (SOC) value of the battery management system based on the first current information collected by the first current collection module and the second current information collected by the second current collection module.