In Missouri, there is a unique predator complex that likely suppresses soybean aphid (Aphis glycines Matsumura) populations prior to reaching economic threshold. Our prior research has shown that when soybeans are infested with aphids under normal growing conditions, populations do not become well established. However, when plants are caged to exclude predators, populations grow rapidly. To determine which predator is most responsible for control of aphid numbers, we caged soybean plants with different size meshes. Three sizes of mesh were used; one which excludes all insects (except mites), one which excludes insects larger than thrips, and one which excludes insects larger then Orius spp. As a control, cages were placed over soybean without mesh. Cages were infested with soybean aphid at different plant growth stages; V1, R1, beginning pod set, and beginning pod fill. Five aphids were transferred using a fine camel’s hair brush to the uppermost expanded trifoliate. Aphids were colony reared and of the same ages (<24 hours). Sampling consisted of weekly visual observations of the caged plants for aphids and aphid predators. In particular, Orius spp. (nymph and adult) and coccinelids (all life stages). Information gained from this study will allow us to assess the key aphid predator species at different soybean phenologies.