Abstract: Due to its natural loess large gap between the particles and particles cemented with each other,and thus have a significant structural。Structural changes significantly influence their mechanical properties and stability of soil。Such as slope,tunnel,embankment,excavation and other problems of practical engineering plane strain used in the theory are mostly based on established remolded,it does not take into account the soils structural。This paper analyzes the engineering properties of loess,Quantitative study of the structural remodeling of loess and loess difference between the mechanical behavior,establish the soil strength and stability analysis of the deformation theory,Improve the system of soil mechanics,guidance the engineering practice。