The marine acidic gas in Zhongyuan Oilfield is mainly distributed in the Puguang gas field in northeastern Sichuan, with characteristics such as “burial permeability, high H2S and CO2 content, and strong edge and bottom water”. As the gas field development enters the middle and later stages, there are problems such as continuous decrease in formation pressure, water invasion, and increasingly serious sulfur deposition. Through self-developed large-scale water invasion and water control experimental models, mechanism experiments were conducted. The research showed that during the water invasion process, the overall water invasion of the model was relatively uniform, while some parts of the water body were affected by conditions such as pore infiltration, and local advances were faster. During the process of injecting gas and controlling water, the gas is influenced by its flow and diffusion characteristics, resulting in a faster and more uniform gas propulsion speed, with some areas experiencing sudden advances. The dip angle of the stratum and the multiple of water bodies affect the water invasion and gas injection water control effect. Overall, when the water energy increases by 1 times, the water invasion amount increases by about 0.5 times; The best effect of injecting gas and controlling water before water invasion occurs is to reduce the amount of water invasion by 2/3, followed by injecting gas at the front edge of water invasion, reducing the amount of water invasion by 1/3. The effect of injecting gas and con-trolling water in the flooded area is not significant. It is recommended to develop a gas and water injection plan based on the scope of water invasion and the actual situation of water flooding. The research results have practical guidance and reference significance for the development of similar gas reservoirs.