Abstract: The open-pit mine coal underlying the slopes backfill mining can effectively improve the recovery of coal, reduce the loss of mineral resources and reduce environmental pollution. The filling equipment in the backfill mining process is the most important equipment for the entire filling system. According to the needs of the backfill mining operation of Delong open pit coal mine, the self-moving filling and retaining equipment was independently developed. The equipment can be operated for different coal seam inclination angles during the filling process, mainly consisting of the walking support device and the baffle device, which can be unmanned operation during the backfill mining process.