The marine target layer in the Daqing Chuanyu block has the characteristics of high formation pressure, high H2S content, high production, and the need for large-scale acid fracturing transformation. The operating conditions of gas wells are harsh, and safe mining is difficult. According to the principle of double well barrier, and based on the two stages of well construction and production, the risk points of integrity failure such as double corrosion, casing wear, strength failure of completion string, and obstruction during lowering were identified. The integrity technology system structure was proposed, and four key evaluation technologies were formed. For dual corrosion, indoor experiments and corrosion prediction techniques are used to optimize the anti-corrosion process of nickel based alloy materials; Establish a crescent shaped eccentric wear prediction model for casing wear, accurately characterizing the remaining wall thickness and strength; A mechanical analysis model was established to optimize the insertion parameters of the completion string in response to the risk of blockage in the open hole segmented completion string; Aiming at the complex stress of acid fracturing completion string, a mechanical model of acid fracturing completion string was constructed using the fourth strength theory to clarify the risk points of the string; In response to the risk of string failure during long-term operation, the wellbore inspection process was tested, and the lifespan was predicted, achieving precise integrity management. The application effect of the pilot test zone shows that through the system’s integrity design and evaluation, the safety and economic production of the three high gas wells are effectively ensured.