The invention is suitable for the technical field of electronic products and provides a shell structure.The shell structure comprises an upper shell, a lower shell, a middle shell and a fixing middle frame.The upper shell and the lower shell are oppositely arranged, the middle shell is connected between the upper shell and the lower shell and is made of metal, and the fixing middle frame is arranged among the upper shell, the lower shell and the middle shell to be fixedly connected with the upper shell, the lower shell and the middle shell.The fixing middle frame comprises a side plate with an inserting hole and an annular wall.The middle shell comprises a fist middle shell body and a second middle shell body which surround the two sides of the annular wall.The annular wall is provided with a first convex rib and a second convex rib.The first middle shell body is provided with a first barb embedded with the first convex rib, and the second middle shell body is provided with a second barb embedded with the second convex rib.According to the shell structure, the first middle shell body and the fixing middle frame are firmly combined together in the mode that the first convex rib is clamped into the first barb, similarly, the second middle shell body and the fixing middle frame are firmly combined together in the mode that the second convex rib is clamped into the second barb, and therefore the tilting phenomenon generated when the first shell body and the second shell body fall down is avoided.