The invention discloses an insulation angle ring and a manufacturing method thereof for a transformer winding. The manufacturing method includes folding one side of a small corrugated paper board in 0.5 mm in the size equal to the difference between the height of a winding wire turn and 1-1.5 mm according to the height and the width of the winding wire turn, folding again in the size equal to the width of the winding wire turn, and finally folding third times in the size equal to the height of the winding wire turn to manufacture a U-shaped insulation angle ring. A high-voltage winding end and a wire turn at the tail end are wrapped by several U-shaped insulation angle rings additionally, and the U-shaped insulation angle rings are directly fastened on the inner side or the outer side of the winding wire turn and then sparsely wrap the same. By the insulation angle ring and the manufacturing method thereof, creepage distance between two sides of the wind wire turn is greatly improved by improving small angle rings of the winding wire turn, and operation efficiency is improved.