The invention discloses a high-intensity damage-free type flexible roughened surface geomembrane and a producing method of the high-intensity damage-free type flexible roughened surface geomembrane, belonging to the field of production of a geomembrane. The high-intensity damage-free type flexible roughened surface geomembrane comprises a geomembrane body. The high-intensity damage-free type flexible roughened surface geomembrane is characterized in that the geomembrane body is in a monolayer calendaring membrane structure; and taper convex points are calendered on the upper surface and/or the lower surface of the membrane body. The main raw materials of the geomembrane comprise ethylene-alpha olefin copolymer, high-intensity polyethylene, high-pressure low-intensity polyethylene, antioxygen, ultraviolet light absorber and carbon black. Compared with the prior art, the high-intensity damage-free type flexible roughened surface geomembrane disclosed by the invention has the characteristics of simplicity in production technique, excellent performance index, and the like, can be widely applied to a railway anti-shock layer, a refuse landfill, a tunnel, a reservoir, a canal, a sewage treatment tank, a landscape lake and other environment-friendly anti-seepage projects, and has very good popularizing and applying values.