The invention discloses a pipe flange protection cover and aims to solve the problems that an existing pipe flange protection cover is molded or cast through a die as required, the production cost is high, dimension adaptability is low, the existing material is not breathable, the pipe is easy to heat and expand, and accordingly the flange cover is dropped off; in addition, since the existing material is excessively heavy, the transportation cost is increased. The pipe flange protection cover is characterized in that the lower end and bottom are made of polypropylene non-woven fabric or composite leather, the upper end is made of soft material and forms an opening end in a surrounded manner, and an adjusting part used for adjusting the diameter of the opening end is arranged on the side wall. The bottom and side wall of a pipe flange protection cover body is made of the polypropylene non-woven fabric or composite leather, the cover has the advantages of breathability, environment protection, wear resistance, oil prevention, water prevention, solar radiation aging resistance and small specific gravity, the temperature in a tube is decreased effectively, the transportation cost is reduced greatly, the diameter of the opening end can be adjusted so that the cover can be adaptive to pipes with different diameters, production cost is reduced, and the unforeseen effect is achieved.