To study the fatigue performance of nano-modified recycled concrete, the fatigue life was estimated and fatigue equations were developed. Fatigue cycle loading tests at different stress levels (0.75, 0.80, 0.85) were designed with different recycled aggregate replacement rates (0%, 30%, 50%, mass fraction) and nano-CaCO3 content (0%, 1%, mass fraction) as the main influencing factors. The results show that the elastic modulus of concrete decreases with the increase of recycled coarse aggregate replacement rate, and incorporation of nano-CaCO3 can improve the elastic modulus, optimize the damage pattern of concrete and effectively enhance its integrity. The overall fatigue life under cyclic load decreases rapidly with the increase of maximum stress level, and 1% nano-CaCO3 modification can increase the fatigue life by 60%. Establish the fatigue life equation with a two parameters S-N (stress level-fatigue life) curve, and deriving the P-S-N curve considering the life probability. The correlation coefficient obtained decreases rapidly with the increase of recycled coarse aggregate substitution rate and increases after nano-modification. The fatigue strain evolution of recycled concrete basically conforms to the three-stage strain curve development law. A new equation is proposed to describe the second-stage strain curve of recycled concrete, and the relationship equation between deformation volume and cycle ratio is established.