To investigate the effect of temperature and relative humidity (RH) on the absorption kinetics of self-activated and moisture-activated O2 scavengers for packaged food, kinetic parameters of each O2 scavenger were evaluated at 43%, 75% or 100% RH and at 10, 25 and 40 °C respectively. Absorption kinetics was well described by a first-order reaction with an Arrhenius type behaviour. For moisture-activated O2 scavengers, a proper high RH was needed to ensure a high O2 absorption capacity, as average O2 absorption capacity was 3.82 mL at 43% RH and 43.40 mL at 75% RH. When the temperature increased, O2 absorption rate constant ascended from 10 °C to 40 °C on an average of 0.153 and 0.306 h−1 in moisture-activated and self-activated O2 scavengers respectively. We could take the effect of temperature and RH into account when we chose different types of iron-based O2 scavengers for packaged food.