Cubic　Cu2O　micro/nanocrystals　were　successfully　synthesized　by　liquid-phase　reduction　using　copper　salt　of　CuSO4　or　CuCl2.2H2O,　and　glucose　or　ascorbic　acid　as　reducing　agent,　respectively.　The　activity　of　the　catalysts　was　evaluated　by　light-off　curves　of　CO　self-sustained　catalytic　combustion　via　temperature-programmed　oxidation　of　CO　(CO-TPO),　with　the　results　showing　the　activity　of　catalysts　following　the　order　of　Cu2O-ClGLU　＞　Cu2O-S-GLU　＞　Cu2O-S-AA　＞　Cu2O-Cl-AA,　(Cl　denotes　CuCl2.2H2O,　GLU　denotes　glucose,　S　denotes　CuSO4　and　AA　denotes　ascorbic　acid,　respectively),　corresponding　to　the　ignition　temperature　of　109　degrees　C,　122　degrees　C,　137　degrees　C　and　186　degrees　C,　respectively.　The　crystal　structure,　elemental　valence,　morphology　and　redox　property　of　the　prepared　catalysts　were　analyzed　by　using　various　characterization　techniques.　Combined　with　in　situ　infrared　spectrum,　the　CO　self-sustained　catalytic　combustion　over　Cu2O　catalysts　mainly　follows　the　Mars-van-Krevelen　(M-v-K)　mechanism:　the　adsorbed　and　activated　CO　reacts　with　lattice　oxygen　to　yield　CO2　and　oxygen　vacancy,　and　then　the　oxygen　vacancy　can　be　replenished　by　gaseous　oxygen.　Combined　with　catalytic　performance　of　high-concentration　CO,　it　is　found　that　the　catalysts　prepared　using　glucose　as　reducing　agent　are　more　angular　compared　with　ascorbic　acid.　The　Cu2O-Cl-GLU　synthesized　with　glucose　and　CuCl2.2H2O　exhibits　the　best　catalytic　activity　among　all　the　catalysts　tested,　attributing　to　its　more　obvious　edge　and　rough　crystal　surface.　The　unique　structure　of　Cu2O-Cl-GLU　leads　to　the　high　exposure　rate　and　coordination　unsaturation　of　atoms　on　the　cubic　Cu2O　micro/nanocrystals　that　can　improve　the　ability　of　activating　gaseous　O2　and　low　temperature　reducibility,　and　consequently　facilitating　the　catalytic　activity.