The grain bulk in its environment is presented as an ecosystem, comprising biotic (grain, insects, microflora) and abiotic (dockage, intergranular air, water vapors, storage structure) elements. The effect of the stored grain bulk environment and microenvironment on each of the system components is analyzed, and the possible implications of these effects in the cause or prevention of grain storage losses are discussed. The interrelation of the biotic and abiotic elements (variables) of this ecosystem, interacting with each other in causing storage losses, is also considered. It is suggested that the ecosystem approach for evaluating the potential loss of stored grain in a given storage site can be used not only to assess the present status of damage and the storability of grain, but also to indicate the steps needed to prevent losses.