The invention discloses a treatment process for oxygen pressure acid leaching slag of lead copper matte and belongs to the field of comprehensive recycling of non-ferrous metal metallurgy. The process comprises the following steps of: the first stage: (1) pre-immersing lead copper matte by a pre-immersing solution, then performing oxygen pressure acid leaching to obtain acid leaching slag and a leachate, and then performing cyclone electrodeposition on the leachate to obtain electrodeposited barren liquor and a metal copper; (2) washing the acid leaching slag obtained in the step (1) by the electrodeposited barren liquor obtained in the step (1) to obtain a filtrate and a filter residue; and (3) adding auxiliary materials into the filter residue obtained in the step (2) to proportion, and then reducing and smelting the mixture to obtain flue gas, coarse lead and slag; a second stage: taking the filtrate generated in the step (2) in the first stage as a pre-immersing liquid in the step (1) in the second stage, wherein other operations are as same as those in the first stage; and in a follow-up stage, circulating the second stage. The process is short in flow and simple to operate. The filtrate obtained by washing the acid leaching slag by the electrodeposited barren liquor in the previous stage serves as the pre-immersing liquid in the next stage to pre-immerse the lead copper matte and no residual liquid wastes are discharged.