The　porous　carbon　(CKC-X-Y,　CKC　is　the　corn　kernel-derived　carbon;　Xis　the　activation　temperature;　and　Y　is　the　KOH/CKC　mass　ratio　(2,　3,　4,　and　5))　adsorbents　were　prepared　from　corn　kernels　by　the　KOH　activation　method.　Textural　property　and　oxygen　functional　group　amount　of　the　CKC-X-Y　sample　were　influenced　by　the　activator　amount　and　activation　temperature.　Among　the　CKC-X-Y　samples,　the　CKC-900-3　sample　displayed　the　highest　surface　area　(1943　m(2)/g)　and　the　largest　pore　volume　(1.10　cm(3)/g),　whereas　the　CKC-900-4　sample　possessed　the　highest　amount　(45.5　%)　of　oxygen　functional　groups.　The　CKC-900-4　sample　exhibited　the　largest　CO2　adsorption　capacity　(3.63　mmol/g　at　25　degrees　C)　among　all　of　the　CKC-X-Y　samples.　The　results　indicate　that　the　activated　corn-derived　porous　biochar　with　a　high　surface　area　and　a　high　oxygen　functional　groups　amount　possessed　a　large　CO2　uptake.　In　addition,　the　CKC-X-Y　samples　showed　high　CO2/N-2　selectivity,　good　recyclability,　and　easy　regeneration　behavior.　The　adsorption　of　CO2　was　physically　and　chemically　adsorbed　on　the　surface　of　the　CKC-X-Y　samples,　with　the　physical　adsorption　being　dominant.　In　which　CO2　was　mainly　chemically　adsorbed　on　the　samples　with　hydroxyl　groups.