Hinge structure of casement window

The utility model relates to the technical field of hinges, in particular to a hinge structure of a casement window. The hinge structure comprises a frame body mounting plate, a fan body mounting plate, a supporting block and a guide plate, the supporting block comprises a first transverse flat section, an inclined section and a second transverse flat section which are sequentially connected, the second transverse flat section is higher than the first transverse flat section, a receding interval is formed between the bottom face of the second transverse flat section and the frame body mounting plate, a plurality of positioning holes are formed in the frame body mounting plate, and the guide plate is arranged in the positioning holes. The plurality of positioning holes are combined to form a first positioning hole group and a second positioning hole group which are distributed on the left part and the right part of the frame body mounting plate; and each positioning hole of the first positioning hole group is