The invention relates to a production technology of a planar high-purity molybdenum target material and discloses a method for producing a large high-purity molybdenum planar target material for flat panel displays, comprising the steps of: molybdenum powder analysis, powder selection, powder blending, die filling, pressing, sintering, rolling, annealing, width milling, wire cutting of end faces,chamfering and grinder machining. The planar high-purity molybdenum target material machined by the method has the following beneficial effects that: the length of the molybdenum target material can be up to 2700mm; the molybdenum content is greater than or equal to 99.95%; the relative density is greater than or equal to 99%; the grain structure is uniform; the flatness is less than 0.05; the surface roughness is Ra0.2; the surface is free of the defects such as flaws, peeling, folding, dents, metal or nonmetal pressed articles and the like; the lengths of internal flaws in the target material are not greater than 0.04mm; and no air bubbles and large crystals are generated.