Fusarium virguliforme (FV), the casual-agent of soybean sudden death syndrome (SDS), and Aphis glycines, the soybean aphid, are widespread and can occur simultaneously in North America. It was unknown whether they interact on shared host plants. Field studies were conducted to determine whether FV influences soybean aphid population growth rates and if soybean aphids influence SDS development. Caged soybean plots were established in Rosemount, MN and Nashua, IA in 2017 and 2018 with four treatments: plots with no aphids or FV, plots infested only with aphids, plots infested only with FV, and plots infested with aphids and FV. Aphid counts and foliar SDS incidence and severity were recorded weekly. At crop maturity, 16 plants per plot were sampled and visually assessed for root rot severity. A logarithmic model of aphid population growth was fit to each plot and the model coefficients were analyzed using a linear mixed effect model to determine whether SDS influenced aphid population growth. Results from preliminary analysis suggest that SDS may have a negative effect on aphid population growth. Other potential interactions between soybean aphid and FV are being explored.