Abstract: As a low cost and easy to operate technology, the solidification/stabilization is widely used for remediating contaminated sites. PAHs leachability and unconfined compressive strength (UCS) of cement-based solidified/stabilized materials with or without activated carbon were evaluated. When the contaminated soil was leached under three scenarios of neutral precipitation, acid precipitation, and co-disposal, the leaching concentrations of PAHs were 2.53, 2.74 and 3.88 μg/L, respectively. After treated by cement of 20% soil weight, the leaching concentrations of PAHs were 8.99, 10.12 and 10.99 μg/L, respectively under the three scenarios. The leachability of PAHs increased when contaminated soil was solidified/stabilized by cement. PAHs concentrations in leachates were in the order of co-disposal scenario>acid-precipitation scenario>neutral-precipitation scenario. When the contaminated soil was treated by 20% cement and 1% activated carbon of soil weight, the leaching concentrations of PAHs was 0.99 μg/L; the addition of activated carbon can significantly lower PAHs concentrations in leachates. 28 d UCS of solidified/stabilized materials was 1.82, 5.95 and 12.06 MPa when the contaminated soil was treated by cement of 10%, 20% and 30% of soil weight, respectively. UCS of solidified/stabilized materials increased with the adding amounts of cement. When the contaminated soil was treated by 20% cement, UCS of solidified/stabilized materials was not affected by the amount of activated carbon when adding no more than 2% of soil weight.