The invention discloses an adaptive multi slope droop control system and an adaptive multi-slope droop control method for a direct current microgrid. Aiming at the problem that in the direct current microgrid, the system average current is contradictory with busbar voltage deviation in distributed microsource parallel operation, a load current is divided into three areas including a light load area, a rate load area and a heavy load area, and then multi slope droop control (MSDC) is implemented for the different load areas, to focus on improvement of system average current performance and busbar voltage deviation of the rate load area and the heavy load area. An MSDC converter output characteristic curve is different from a traditional constant droop output characteristic, the light load area, the rate load area and the heavy load area in the load area can be flexibly distributed according to system requirements on average current error and busbar voltage deviation, and an adaptive adjustment capacity to the load is provided, so that optimal configuration and design for the droop characteristic within a relatively wide load range can be achieved.