In this study, both commercial activated carbons (ACs) and chemically activated ACs were prepared and studied for the adsorption and desorption properties for volatile organic compounds (VOCs). The ACs with large surface areas have a high adsorption capacity for VOCs. However, their desorption efficiency is significantly low due to their complex pore structures and molecular size of VOCs. For enhancing the desorption rate, various in situ vacuum conditions (full vacuum, different pump speed and pressure, and vacuum with inflow) and the vacuum-heating combination system were applied. The desorption rate was observed to increase up to 40% under the condition where vacuum was supplied with inflow, and up to 85% in the combined system. In addition, the desorption mechanism operating in the vacuum condition was also studied.