Seepage control and reinforcement of grotto temples is an important measure for conservation of grotto statues. In recent years, along with the rapid economic development across the country, a large number of conservation projects for cultural relics in China have been implemented. However, follow-up studies of the effects of conservation on grotto temples remain relatively few. Hangzhou Feilaifeng statues, one of the national key cultural relics, have suffered from serious seepage diseases, which have resulted in damage and threats of damage. Since 2005, two stages of a conservation project have been implemented in the areas of Feilaifeng statues. Reinforcement of dangerous rocks, fracture grouting and surface seepage control have been included. Real-time tracking and evaluation of the seepage-control effects of the project is of important reference value for follow-up stages of the project and conservation of other similar grotto statues. Combining engineering data, on-site observations and measurement of seepage and analysis of seepage exudates, we made a tentatively quantitative evaluation of the seepage-control results after the second-stage conservation project. This work can provide a reference for evaluating the effects of conservation projects for grotto temples in rainy areas of southern China.