Mushrooms have been grown commercially on many different substrates for years, usually agricultural by-products such as straw or stover. Increased popularity for specialty mushrooms with consumers has led to increased production and great demand for economic substrates. Oyster mushrooms are easier to grow relative to other types of mushrooms and their production has increased dramatically in recent years. This study examines the economic feasibility of using soybean hulls as a primary substrate for oyster mushrooms, replacing traditional wheat straw. The study uses a cost-benefit analysis to determine an optimal substrate based on yield and the number of crops harvested per year. The study shows that soybean hulls, combined with corn gluten or soybean meal increases yield 4.5 times, which more than offsets for higher costs for soybean hulls. The use of soybean substrate also allows a producer to raise about four more crops per year, which in turn uses fixed resources more efficiently and increases profitability.