The utility model discloses a mobile power supply device comprising a box body which is internally provided with a wire take-up device. The box body is provided with a wire plug outlet. A top surface of the box body is provided with a control display panel and a socket. The box body is also provided with a box cover which covers the top surface of the box body. The mobile power supply device has the advantages that the time of sorting out a power disk cable due to cable tangle of an ordinary power disk is shortened, the work efficiency is effectively raised, the box cover is closed in transportation, and the control display panel and internal components are effectively protected from being damaged.