To provide a cargo handling auxiliary facility capable of positively preventing intrusion of rain which can be installed without providing a roof on a building even when a wall of the existing building is broken to make an opening for loading and unloading of cargos.

The cargo handling auxiliary facility 6 bridging a vehicle and the opening 4 of the building 1 for carrying out loading and unloading work of cargos is composed of a portal structural body 7 with a roof, a cover member 13 covering an upper face and both right and left side walls of the structural body 7, a sealing member 15 provided around a front side opened part 14 of the structural body 7 and having flexibility of sealing a gap between a rear end part of the vehicle in the structural body 7 and the front side opened part 14 of the structural body 7, and eaves 16 provided so as to protrude forward in an upper part of the structural body 7. A rain cover 73 is provided so as to protrude forward on both right and left side walls of the structural body 7.