The invention discloses a method for analyzing a relationship between deformation of a foundation pit and ground subsidence outside of the foundation pit. The method is characterized by confirming a relational expression between the deformation and soil body subsidence outside of the foundation pit according to three basic deformation features of a foundation pitenclosing structure, and including decomposing an enclosing structure deformation mode, collecting soil body subsidence volumes outside of the foundation pit on site, building an inversion expression, processing data by using a diagonal cross least square method, fitting subsidence data by using a difference evolutionary algorithm (DE), reasonably selecting a zoom factor F and a crossover probability Cr of the DE, generating and evaluating simulated data and the like. The method for analyzing the relationship between the deformation of the foundation pit and the ground subsidence outside of the foundation pit obtains optimal values of the zoom factor F and the crossover probability Cr by analyzing influences of the zoom factor F and the crossover probability Cr in an algorithm, and uses the diagonal cross least square method as a difference selection function for inversion calculation. The method for analyzing the relationship between the deformation of the foundation pit and the ground subsidence outside of the foundation pit aims at obtaining maintaining deformation conditions by monitoring the soil body subsidence outside of the foundation pit and forecasting deformation in future phases, and can be widely used in prediction studies available for the corresponding relationship between the ground subsidence outside of the foundation pit and enclosing deformation.