PURPOSE: To obtain a supporting body having excellent adhesion property with a photographic emulsion layer by applying a gelatin soln. of specified gelatin concn. under specified conditions and drying to form a gelatin base coating layer.

CONSTITUTION: This supporting body consists of a sheet-like base body, coating layers essentially comprising a polyolefin resin formed on both surfaces of the sheet-like base body, and a gelatin base coating layer essentially comprising gelatin formed on the surface of the surface coating layer (surface side to be coated with a photographic emulsion layer). This gelatin base coating layer is formed by applying a gelatin soln. having the gelatin concn. between ≥0.3wt.% and <2.0wt.% by low-pressure air knife coating method under ≤500mmHg air pressure and dried. Thereby, the base coating layer has excellent uniformity of the coating surface and the emulsion layer shows excellent wet- state adhesion property after developed.