Abstract: Due to the coupling effect of freeze-thaw cycle and external load, it is more difficult to characterize the constitutive relationship of fractured rocks in the cold region under the influence of the progressive propagation of the cluster of primary and secondary cracks at the end of the initial defect. Based on the theory of damage localization, the initiation and propagation of macro-crack in rock are modeled as the growth of a cluster of crack tips. The influence of micro-scale freeze-thaw damage in the rock is also considered, resulting in a macroscopic and microscopic progressive damage variable for the rock. Based on Weibull distribution function and M-C strength criterion, a constitutive model of freeze-thaw fractured rock considering localized macro and micro damage effects is constructed, and the theoretical expressions of the model parameters are presented. Nuclear magnetic resonance damage tests and uniaxial and triaxial compression tests of fractured sandstone under freeze-thaw cycles were carried out to quantitatively analyze the relationship between the number of freeze-thaw cycles and rock porosity and damage evolution. The effects of freeze-thaw cycles and confining pressure on progressive damage mechanical properties of rock were studied, and the rationality of the model was verified. The results show that: The freeze-thaw cycle leads to fracture expansion and pore structure change in rock, which significantly reduces rock strength and stiffness. The constitutive model can accurately characterize the whole process of deformation and failure of frozen and thawing rock under load, and can reflect the influence of freeze-thaw cycle and confining pressure on the deformation characteristics of rock. The microscopic damage of rock during the freeze-thaw cycle is caused by the initiation of micropores in the early stage and the growth of pore size in the late stage. The sensitivity analysis of model parameters reveals the influence of freeze-thaw cycle and confining pressure on the mechanical response of rock. Confining pressure can effectively inhibit the growth of macroscopic damage of rocks, while the increase of freeze-thaw cycles accelerates the accumulation of microscopic damage of rocks, resulting in the decrease of peak strength of rocks, the decrease of ductility of rock and the gradual appearance of brittleness. Damage correction coefficient η plays an important role in describing the transition between plastic deformation and brittle failure of rock. The damage correction coefficient η plays an important role in describing the transition between rock plastic deformation and brittle failure. For further analysis of crack damage evolution law of rock under freeze-thaw environment provides a theoretical reference.