A current sharing method and device for a DC power supply are provided, and the method includes: taking a latest detected bus current as a reference current to perform current sharing control on a local host current; calculating and timing sending time of the local host current according to the latest detected bus current, the local host current, and a preset corresponding relationship between a difference between the local host current and the bus current and the sending time of the local host current, and if no new bus current is detected within a timing time, sending the local host current as a new bus current to a bus when the timing times out. The method has small communication traffic and no master-slave relationship, and is simple to control, which reduces the difficulty of system development and improves the system reliability.