The gas well in Gaomo block is faced with severe and complicated plugging problems in the late development process, which seriously restricts the stable and upper production of the gas field. Based on the blockage phenomenon of Dengying formation gas well and the composition characteristics of the blockage, this paper analyzes the source of the blockage of Dengying Formation gas well. It is believed that the main blockage of Dengying Formation gas well is Fe-containing compounds, and the blockage comes from the corrosion products of tools and pipe strings in the horizontal section of the well. The clogging mechanism of the gas well was identified through downhole corrosion detection, downhole corrosion environment analysis, and indoor corrosion test of the horizontal section tubing material. It was believed that the clogging occurred due to the bonding, cementation and accumulation of inorganic corrosion products and organic matter in the horizontal section in the slow flow area of the lower wellbore. After entering the production system with the production air flow, it accumulates at the reducing and turning positions of the tubing. Based on big data analysis and neural network model, a gas well clogging prediction mechanism was established by using gas well production statistics. Existing clogging removal measures were classified into two categories: wellhead and underground clogging removal measures according to the location and degree of clogging, and the applicability, advantages and disadvantages of each clogging removal technical measure were summarized respectively. Some theoretical basis and technical reference are provided for the prevention and treatment of gas well blockage in the gas field.