In order to study the carbonation resistance of recycled concrete with different content of recycled coarse aggregate and different content of fly ash and the performance change of recycled concrete after a period of carbonation, this study carried out indoor carbonation test and electron microscope scanning analysis on samples with different content of fly ash (0%, 20%, and 40%) and different content of recycled aggregate (0%, 50%, and 100%). The results show that: the carbonation depth of recycled concrete increases with the increase of recycled coarse aggregate and fly ash content. The carbonation rate of recycled concrete decreases with the increase of carbonation time. The greater the compressive strength of recycled concrete, the smaller the carbonation depth, and the regression equation between compressive strength and carbonation depth after different carbonation time was obtained by fitting the experimental results.