In the present study, a porous concrete with alkali activated slag (AAS) and coal bottom ash was developed and theeffect of carbonation on the physical property, microstructural characteristic, and heavy metal leaching behavior of the porousconcrete were investigated. Independent variables, such as the type of the alkali activator and binder, the amount of paste, and CO2concentration, were considered. The experimental test results showed that the measured void ratio and compressive strength of thecarbonated porous concrete exceeded minimum level stated in ACI 522 for general porous concrete. A new quantitative TGanalysis for evaluating CO2 uptake in AAS was proposed, and the result showed that the CO2 uptake in AAS paste wasapproximately twice as high as that in OPC paste. The leached concentrations of heavy metals from carbonated porous concretewere below the relevant environmental criteria.