A coating apparatus for coating a conveyed support with an emulsion for a photographic light-sensitive material by letting the emulsion flow down between a pair of edge guides so as to form a curtain layer of the emulsion. The apparatus includes a slide surface, having a slit and inclined for a predetermined angle to the horizontal axis, for supplying the emulsion; side plates provided on both edges of the slide surface; the pair of edge guides each provided on respective one of the edges; and plural solution injecting outlets, each provided on respective one of the side plates, for supplying auxiliary solution; in which a coating operation of the conveyed support with the emulsion is conducted while the auxiliary solution is being flowed down along the edge guides at a flow rate between 0.3 cc/min. and 3.0 cc/min. from each of the solution injecting outlets.