In order to explore the carbonation performance of fly ash concrete under the influence of various factors，the carbonation tests of concrete with 0%，10%，20% and 30% fly ash were carried out under the action of single freeze-thaw cycle，single dry-wet cycle and freeze-thaw-dry-wet cycle respectively.The results show that the carbonization depth increases exponentially with the increase of cycle times； under the same environment，the higher the fly ash content，the greater the carbonization depth； with the increase of age，the carbonization depth increases gradually； under the same age（7d，14d，21d，28d）and fly ash content（0%，10%，20%，30%），the freezethaw-dry-wet-carbonization depth ＞freeze-thaw-carbonization depth.According to the test results，the carbonation model of fly ash concrete is established，which can simulate the carbonation depth of fly ash in different environments，fly ash content and carbonation time，and can provide help for engineering practice.．