The invention discloses a welded type planar film spray nozzle, comprising a spray pipe, water film plates and a baseplate, wherein, the spray pipe and the water film plates are made of stainless steel; two spray channels of the spray pipe are a split structure and are formed by combining two stainless steel elbow pipes; the baseplate is provided with pilot holes which are matched with the outside diameter of the two stainless steel elbow pipes; the two stainless steel elbow pipes are respectively installed in the pilot holes and are welded and fixed, the injection orifices of the two stainless steel elbow pipes are arranged in a reverse symmetry manner; the two water film plates are vertically welded on the baseplate and are respectively corresponding to the injection orifices of the twostainless steel pipes; and the bending radius of the stainless steel elbow pipes range from R20 to 40 mm, included angles formed by the end faces of the injection orifices and the water film plates range from 25 to 30 degrees, the film forming faces of the water film plates are pressed into special molded lines, a cambered face is arranged on the top thereof, the corner radius thereof ranges fromR30 to 40 mm, the length of the water film plates ranges from 100 to 120 mm, and the width ranges from 60 to 80mm. Compared with the existing film spray nozzle, the welded type planar film spray nozzle has the advantages of no rusting, scouring resistance, long service life, stable formed water film, smooth surface, small waterline, large area of water film, etc.