Little research has been mode on freezing and thawing landslides in Shanxi, a typical seasonally frozen soil area, but landslides caused by freezing and thawing every year are frequent. Therefore, in this paper the undisturbed Malan loess in Lyuliang area of Shanxi Province was taken as the research object. Through the static triaxial shear test and microstructure test under different initial water content and different freeze-thaw cycles on the Q3 loess in this area, the effects of freeze-thaw on the mechanical properties of loess were investigated. The results show that as the number of freeze-thaw cycles increases, the moisture content decreases to varying degrees. The freeze-thaw cycle makes the soil easier to yield during shearing. When the confining pressure and moisture content are constant, the failure stress of the soil generally decreases with the superimposition of freeze-thaw cycles. The influence of moisture content on the growth of deviatoric stress is greater than that of freeze-thaw cycle. The strength parameters of loess follow the freeze-thaw cycles in the manner that the cohesive force decreases exponentially with the number of freeze-thaw cycle, and the internal friction angle hardly changes. At the same time, with the increase in the number of freeze-thaw cycle, large particles are broken into small particles and clastic aggregates, and the void ratio increases. The results of this study can provide a reference for the study of the mechanism of landslides caused by freeze-thaw in Lyuliang area.