The utility model belongs to the technical field of sunhats, and discloses a folding sunhat. The safety helmet is mainly technically characterized by comprising a helmet top, helmet cloth and a fixing
bandage, a supporting ring is arranged on the periphery of the helmet cloth and comprises at least two sector-ring-shaped sub-rings, a positioning and
locking mechanism is arranged at the joint of every two adjacent sub-rings, each positioning and
locking mechanism comprises a connecting body, U-shaped inserting grooves are formed in the two ends of each connecting body, and the U-shaped inserting grooves are connected with the helmet top. A U-shaped slot is formed in the cap top, the axial direction of the U-shaped slot is consistent with the axial direction of the cap top, side clamping grooves are formed in the clamping plates on the two sides of the U-shaped slot, a bottom clamping groove is formed in the bottom of the U-shaped slot, plugs matched with the U-shaped slot are arranged at the two ends of the
branch ring, side protrusions are arranged at the positions, corresponding to the side clamping grooves, of the two sides of each plug, and the side protrusions are matched with the bottom clamping groove. The top of the plug is provided with a top protrusion corresponding to the bottom clamping groove, the side protrusion is inserted into the side clamping groove, the sunshade area is large, the structure is simple, carrying and using are convenient, cost is low, and damage is not prone to occurring.