In order to solve the severe carbonization problem in hot and humid regions， the hot and humid environment were simulated in laboratory， the carbonization test was conducted and the effects of particle size and use level of super absorbent polymer（SAP） on the carbonation resistance of concrete were investigated. By using scanning electron microscope（SEM）， concrete microscopic morphology before and after carbonation test were identified， and based on mercury intrusion meter（MIP）， the pore structures of the concrete at different layers were determined. The results show that the incorporation of SAP can effectively improve the concrete carbonation resistance， and the carbonation resistance improved significantly with the increase of carbonization age. Although the incorporation of SAP increases the porosity of concrete， it refines the pore structure between each layer and reduces pore connectivity. Furthermore， after SAP releases water， a higher density region is formed outside the pores， and SAP promotes hydration to fill these pores， it also reduces the amount and size of crack， thereby SAP internal curing concrete can inhibit the diffusion of CO₂ and promote the carbonization resistance of concrete.