Abstract: Stored grain pests have developed resistance against almost all kinds of pesticides and fumigants due to frequent and non-proper use of pesticides and fumigants. In postharvest ecosystems, the development of insecticide resistance among stored grain pests has threatened the global food security. Comprehensive detail of common mechanisms behind pesticide resistance in stored grain pests has been described in this review. The different resistance mechanisms stored grain pests usually developed to cope with pesticidal stress, include physiological mechanism, behavioral mechanism and biochemical mechanism. All the aspects of resistance mechanisms should be known in order to design effective strategy for the proper control of target pest.