The invention provides a heat dissipation explosion-proof arc-proof cable joint protection box. The heat dissipation explosion-proof arc-proof cable joint protection box comprises a protection box body, and the protection box body comprises a shell and necking extraction portions arranged at the two ends of the shell. A cavity used for containing a cable is formed in the shell, and a heat conduction inner container layer and a heat dissipation layer are sequentially arranged between the shell and the cavity from the shell to the cavity. The heat conduction inner container layer is an aluminumoxide ceramic inner container layer, and the heat dissipation layer is a low-heat-resistance high-heat-conduction material layer. The low-thermal-resistance high-thermal-conductivity material layer isfilled with the following low-thermal-resistance high-thermal-conductivity materials in parts by mass: 54-57 parts of bentonite, 24-28 parts of fine quartz sand, 14-16 parts of water, 2.5-3.5 parts of cement, 0.24-0.26 part of taric acid and 0.24-0.26 part of trisodium carbonate. A strong heat dissipation material is used as the heat dissipation layer, so that heat of a cable can be dissipated intime, and the heat dissipation explosion-proof arc-proof cable joint protection box has excellent performances of high heat dissipation, electric arc prevention and the like.