Abstract: when soil nailing technology is applied in weak soil, the displacement of slope is increased and security of slope is brought down. The composite soil nailing technology (soil nailing and micro-pile) is adopted for practical design of controlling buildings and slope displacement, as well as for measures of construction in saturated silty soil. The effect of composite soil nailing is compared with that of general soil nailing by actual trail and observation. Project practice proves that displacement of excavation can be controlled effectively by composite soil nailing(soil nailing and micro-pile).