The invention relates to an upper cover of a suitcase body. The upper cover of the suitcase body is provided with a frame and a case body face plate, wherein the frame is defined by four side plates, the case body face plate can cover a top opening, a boss bulging to the inner side of the frame is formed at the top of the inner circumferential surface of the frame, the peripheral surface of the case body face plate is attached to part of the bulging surface of the boss, limit edges capable of covering the edge of the top surface of the case body face plate in a lapping manner are formed by extending from the top periphery of the frame to the inner side of the frame, and Z-shaped fixing pieces capable of cooperating with the limit edges to fix the case body face plate at the top of the frame are arranged between the boss and the bottom surface of the case body face plate; each Z-shaped fixing piece comprises parallel cross plates and a longitudinal plate arranged between the two cross plates, one cross plate is attached to the bottom surface of the case body face plate, the longitudinal plate is attached to the residual part of the bugling surface of the boss, the other cross plate is attached to the bugling side surface of the boss, and the longitudinal plate is connected with the boss through a screw. Compared with the prior art, the upper cover is more stable in structure and higher in pressure bearing capacity.