The invention relates to a combustion device special for petroleum forging waste gas. The combustion device comprises a shell, supporting feet are arranged at the bottom of the shell, an feeding inletis formed in the middle of the bottom of the shell, a valve is arranged on the feeding inlet, a heat preservation layer is arranged between the shell and an inner cavity, a heat-resistant plate is arranged at the top of the inner cavity, a combustor is arranged on the heat-resistant plate, a plurality of nozzles are connected to the top of the combustor through fixing pieces, a pressurizing chamber is formed in the bottom of the combustor, a preheating chamber is arranged on the pressurizing chamber, an oxygen pipe and an auxiliary gas pipe are arranged on the preheating chamber, and one-wayvalves and flowmeters are arranged on the oxygen pipe and the auxiliary gas pipe correspondingly; and a gas outlet is formed in the top of the inner cavity, a cooling device is arranged on the gas outlet and connected with a filter device, and the cooling device is connected with a motor on the outer wall of the shell. According to the combustion device, the working efficiency and accuracy are improved through full combustion, structural stability is improved through cooling, pollution is reduced through filtering, environmental protection is improved, and up-to-standard discharging is achieved.