The foundation of Wenzhou shoal project is soft and deep. The stability control issue of building seawalls on the deep soft foundation was solved by using a composite foundation treatment of plastic drainage plates and geotextile, combining with the in-situ monitoring. The in-situ monitoring data of Wenzhou shoal project was analyzed and the settlement prediction analysis was conducted. Basing on the conventional exponential curve fitting method, the settlement prediction model is presented for the classified construction on soft foundation. Considering the non-linear of deformation and soil consolidation with load changes, the model used the settlement deformation characteristics under the last load to predict the settlement development under the next load.