Based on a large number of field data, this paper monitors the deformation of the retaining wall during the excavation of the foundation pit, the settlement of the surrounding surface and the deformation of the wall roof. The monitoring results show that the overall deformation of the retaining wall during excavation is large in the middle and small in the two ends. With the increasing excavation depth of the foundation pit, the deformation of the wall is increasing and the monitoring hole shows a continuous and slow change trend. The cumulative vertical changes of the surface subsidence monitoring point basically show a sinking trend. Although there is a partial subsidence monitoring point where the accumulated subsidence amount exceeds the alarm value range and the alarm condition occurs, from the settlement curve of the surface subsidence monitoring point, the monitoring point shows a continuous and slow change trend, and no mutation occurs. And the sedimentation curve is stable. The vertical monitoring points of the roof are showing a continuous and slow change trend, and the sedimentation curve is smooth. The cumulative plane displacement of the monitoring points in the horizontal direction of the wall is basically displaced toward the inside of the foundation pit, and the horizontal displacement of each monitoring point ranges from 0 to + 9mm. The conclusion is of practical value and provides reference for the design and excavation of foundation pit on soft soil foundation in intensive buildings.