Abstract: As more attention has been paid to urban underground space, anti-floating problems become an important part of geotechnical engineering. Although the anti-floating research for the building service life is relatively thorough, but the probably anti-floating issues caused by construction or hydrogeological condition changes are normally ignored. In recent years, large-scale high-rise buildings and integral underground parking garages are constructed in ridges landform area. Due to the poor permeability of rock and soil mass in ridges landform, and heavy rains from May to August in this area, surface water may destroy underground structures by penetrating into the foundation floor through weak links of trench backfill. Combining with specific cases, anti-floating problems caused by surface water infiltration are studied and the countermeasures are provided, which is of good performances in practice.