Abstract: The Pearl River Delta Water Resources Allocation project has a design service life of 100 years, with the inner steel pipe's anti-corrosion coating designed for 50 years. Based on existing anti-corrosion technologies and research, combined with detailed analysis of the actual geological conditions in the Pearl River Delta, a corrosion protection design featuring “epoxy powder internal anti-corrosion+epoxy polymer-modified cement mortar external anti-corrosion+sacrificial anode cathodic protection” was adopted for the inner steel pipe. Theoretical calculations confirmed its rationality, and the project had been successfully implemented.