Abstract: Abstract: Liu & Carter analyze the differences of deformation properties between structured soils and remolded soils which the Cam-clay model studies. More, they propose constitutive Cam-clay model which is established based on the Cam-clay model to consider the influence of soil structure. The parameters of the constitutive Cam-clay model have definite physical meanings, and this model is widely applied. But the yield stage of compression curve of structured soils in isn’t a straight line and cannot reflect the compression properties of structured soils. It brings inconvenience and error to establish constitutive model. Using the coordinate system, it can replace the non-linear relationship of compression curve in. A modified constitutive Cam-clay model for structured soils in is established.