Seasonal changes and the alternation of day and night produced freeze-thaw cycle effects, which lead to changes in the structure and physical properties of soil in loess areas, and also affected the collapse and deformation characteristics of loess. This article used indoor collapse tests and microstructure tests to analyzed whether the influence of freezing temperature on microstructure was consistent with the response rules of macroscopic collapse deformation. The research results show that: the moisture field and the number of freeze-thaw cycles remain unchanged, the collapsing deformation of loess gradually decreased as the freezing temperature decreases. This phenomenon shows that the freezing temperature determines the freezing rate, and the speed of the freezing rate affects the collapsing deformation of loess. As a result, the cementation force between soil aggregates weakened, the skeleton particles deflected, the particle shape, connection method and distribution arrangement within the soil body changed, and a new stable structure was formed. Quantitative analysis found that the probability entropy, average shape coefficient, distribution fractal dimension, pore area ratio and pore diameter change range all showed regular changes, which was consistent with the qualitative analysis results. This shows that was a good correlation between the change pattern of pore structure inside the soil and the collapsibility pattern of loess caused by the reduction of freezing temperature.