The invention belongs to the field of bridge deck pavement, and particularly relates to hot melting rubber and plastic waterproof bonding modification asphalt mastic used for a large-scale steel box bridge waterproof bonding layer and a preparation method of the rubber and plastic waterproof bonding modification asphalt mastic. The rubber and plastic waterproof bonding modification asphalt mastic consists of the following raw materials in parts by weight: 10 to 20 parts of waste tire rubber powder, 5 to 10 parts of thermoplastic resin, 1 to 5 parts of thermoplastic elastic bodies, 2 to 10 parts of octylene-ethylene copolymers, 2 to 10 parts of terpene resin, 5 to 15 parts of tall oil polyamine carboxylate, 2 to 5 parts of styrene butadiene rubber and 20 to 70 parts of petroleum asphalt. The modification asphalt mastic provided by the invention has the waterproof performance, so the water resistance is realized, the asphalt mastic can still be firmly bonded with the steel bridge desk even when obvious water exists, the asphalt mastic is applicable to waterproof bonding layer and transition layer construction in the steel box bridge asphalt mixture pavement, the waterproof and anticorrosion effects are realized on the bridge deck, the protection effect is realized, a paving layer is carried, and the bonding effect is realized.