The excavation engineering in the vicinity of the existing building lock has a certain effect on the safe operation of it.In order to understand the influence of slope excavation in the foundation pit near the lock and ensure the safety and normal operation of it,we establish a 2D finite element model of the slope excavation in the foundation pit near the lock combining with nonlinear finite element simulation analysis method,ideal elastic-plastic constitutive model and D-P yield criterion.Base on the analysis of the influential factors including the distance between foundation pit and the lock,and slope of the pit,we present the proposed value of the safe distance and excavation slope of the foundation pit near the lock.