Abstract: With the extension of oilfield development time, the water content continues to rise, coupled with the influence of associated media such as H₂S, CO₂, Cl^-, and sand particles, which leads to the increasing corrosiveness of the transported media. At the same time, with the continuous deepening of development layers, the temperature of the produced fluid is also constantly rising, making the service conditions inside the gathering and transportation pipeline more demanding. It is urgent to upgrade the existing pipeline anti-corrosion coating technology to improve the corrosion resistance, high temperature and high pressure resistance, and high temperature and salt resistance of the coating. Based on the research results of using HCC fiber-reinforced composite coatings, five improved new fiber-reinforced inner coatings are designed and prepared, and their macroscopic morphology, thickness, adhesion, high temperature and high pressure corrosion resistance with/without defects,and high temperature salt resistance were tested and evaluated. The research results show that the surfaces of the five new coating samples are smooth and without bubbles, and the coating adhesion is higher than 10 MPa. The cross-sectional morphology shows that the interface between the substrate and the coating is tightly bonded, without cracks or delamination.The results of high-temperature and high-pressure simulated corrosion experiments show that the STA, STF and STK coatings have good performance. Further experiments were conducted on high-temperature salt resistance and high-temperature and high-pressure corrosion resistance with defects. The test results show that the STK coating has the best comprehensive performance and can be used as an upgraded coating for gathering and transportation pipelines under harsh working conditions.