The invention discloses a mower which comprises a casing, wheels, cutting blades, a cutting motor and a power supplying module. A charging slot dented towards the inside of the casing is arranged on the casing, the power supplying module is provided with a charging terminal used for transmitting energy or signals, the charging terminal is arranged in the charging slot instead of exposed outside the casing, therefore the terminal cannot be corroded due to wetting out by rain, poor contact of the charging terminal is avoided, and deformation of the charging terminal caused by collision is prevented. The invention further provides a butt-joint charging system.