The invention discloses an instrument of a lightning protection device. The instrument comprises an upper housing and a lower housing, which are connected together by a buckle. The two housings are connected together on a buckle edge, and a rubber member is disposed on the buckle edge. A protection sleeve used for wrapping the upper housing and the lower housing is provided, and comprises at least three protection layers, which are an alkali-free glass cloth layer, an adiabatic cloth layer, and a silica gel layer. A high temperature resistance fireproof coating layer is disposed on the alkali-free glass cloth layer in a coated manner. The protection layers are disposed on the surface of the instrument, and the instrument is prevented from being burned by the high temperature flame, and the wrapped instrument has good protection effect, firm and simple structure, and convenient use.