The invention provides a connecting structure of a lamp shell and an upper cover of a lamp, which is arranged at the connecting part of the shell and the upper cover of an illuminating lamp and comprises a hanging part and a supporting part, wherein the hanging part is arranged on the upper cover, the supporting part is arranged on the shell, the hanging part is a hook arranged at the periphery of the upper cover, the supporting part is a hinge pin correspondingly arranged on top of the shell, the hinge pin is hinged with the hook part of the hanging part, two supporting plates are arranged in parallel on the outside of the shell, the two supporting plates are correspondingly provided with pin holes, two ends of the hinge pin penetrate the pin holes, and a middle part is arranged at the hook of the hanging part. The invention effectively solves the problem of field maintenance of professional lamps, the time for the uncovering maintenance of the lamp can be markedly shortened, and anti-looseness of the shell and the upper cover is realized, each part in the inner cavity of the lamp is rapidly maintained, and the service life of the lamp is prolonged, thereby the economic loss of a client due to lamp damage is avoided, the maintenance cost is saved, and simultaneously, the market competitive power by adopting the lamp is enhanced to win the market.