The Laohuling Dam site in Liangzhu Ancient City is a typical relic of the earliest large-scale water conservancy project system discovered in China, and is of great significance to the study of the origin of Chinese civilization and the history of world civilization. In order to clearly show the traces of the “grass wrapped in mud” on the soil site, and in view of the problem of protecting soil sites in the warm, humid and rainy environments, we have proposed a set of engineering strategies to avoid the use of chemical materials for reinforcement. These strategies summarize the experience and lessons learned from the protection of domestic soil sites and refer to the research results of Zhejiang University and the engineering experience of Dunhuang Academy. The engineering strategies of “wet method protection + small environment control” include:1) building a light isolation protection shed to inhibit the growth of green organisms; 2) laying a waterproof blanket to control the dam body water seepage; 3) setting up the electric heating glass cover to seal the display surface of the dam body; 4) using a gas-water humidification system to keep constant air humidity and soil moisture content; 5) using plant essential oils and other green environmental protection technologies to control microorganisms; 6) doing a good job in real-time monitoring and management of the site. This comprehensive measure has been applied to the engineering practice of the archaeological section protection of the Laohuling Dam site in Liangzhu Ancient City, Hangzhou. This is a new attempt in terms of the protection concepts and engineering measures of soil sites. Although there are still many shortcomings, it could undoubtedly provide a reference for the protection of similar soil sites in the future.