Lanzhou loess is the typical sulfate saline soil, and the soluble salt in the soil has a significant influence on the physical and mechanical properties of the soil. In order to study the salt effect on the physical and mechanical properties of the Lanzhou loess and compare the variations of the soil properties with and without salt, the desalting experiments on the Lanzhou loess were performed by dipping the soil into the deioned water to soak out the salt in the original soil and then to filtrate for remaining the soil particles. The Atterberg limits of the soil after desalting increase owing to the variation of soil particle composition and grain refining. The shear strength parameters and the uniaxial compressive strength increase after desalting owing to the decrease in calcitic cementation and the variation of soil structure after desalting.