In order to study the deterioration law of compressive strength of fly ash mixed concrete,fly ash mixed concrete speci-mens were prepared with crushed stone,cement,fly ash,medium sand and tap water as raw materials.Under the action of carboniza-tion and dry wet cycle,the strength deterioration test of the specimen was carried out by using the universal pressure testing machine.The test results show that when the content of fly ash does not exceed 30%(including 30%),the compressive strength of the specimen does not deteriorate.When the content of fly ash exceeds 30%,the more the content of fly ash,the greater the deterioration of com-pressive strength.The compressive strength of each specimen increased with the extension of age.Increasing the content of fly ash will improve the deterioration of splitting tensile strength.Prolonging the age will slow down the deterioration rate of splitting tensile strength.Increasing the content of water binder ratio leads to the improvement of splitting tensile and compressive strength deterioration of the specimen.Under carbonization,the compressive and splitting tensile strength of the specimen are improved.When the carboni-zation time is 13 days,the compressive and splitting tensile strength of the specimen reach the peak value.Under the action of dry wet cycle,the compressive and splitting tensile strength of the specimen will deteriorate.When the content of fly ash is 30%,the average compressive and splitting tensile strength of the specimen is relatively high.