The effects of different freeze thaw media and freeze thaw cycles on the freeze thaw resistance and pore structure of concrete were studied through the single side freeze thaw test. Based on the box dimension, the fractal model of the pore size distribution of concrete after freeze thaw cycles was established, and the relationship between the fractal dimension and compressive strength was analyzed. Finally, a multifactor compressive strength model based on compound pore parameters and fractal dimension was established. The results show that the surface morphology, mass loss, relative dynamic elastic modulus, compressive strength, frost durability coefficient and pore structure parameters of concrete under different freeze thaw media gradually deteriorate with the increase of freeze thaw cycles, and the damage of the concrete in salt solution is more serious than in water. The fractal dimension of concrete pore distribution decreases with the increase of freeze thaw cycles. The evolution of pore structure parameters of concrete in the process of the single surface freeze thaw cycle can be divided into three stages:initial stage, middle stage and late stage. The pore parameters which are sensitive to freeze thaw cycle in middle and late stages are average chord length, specific surface area, air content and spacing factor. The regression effect of the multi factor compressive strength with the parameters of the composite pore structure and the fractal dimension is significant. The model can accurately describe the quantitative relationship between the compressive strength and the pore structure of concrete either in water or salt solution after the freeze thaw cycle.