The Corticium foot-rot disease caused by Corticium gramineum Ikata et MATSUURA, occurring particulary on the basal part of wheat stem, is characterized by the dark-brown lesion and later by the decay of stem lesion and infection of young leaves in severe case. The effects of soil types, organic manure, chemical fertilizers such as ammonium sulphate, calcium superphosphate, potassium chloride and lime on the development of the disease were studied by the artificial inoculation during two seasons at Akashi, Pref. Hyogo. The results of these investigations showed that the least injury occurred on the wheat plants grown in the sandy soil in which added organic manure, chemical fertilizers together with lime. The sandy soil seemed to be more unfavorable to the development of the disease than the loam and clay soil. There were marked seasonal changes in the microbial populations with the difference of the soil types and the fertilizers. The severity of the disease generally increased with the number of fungi in soil, while decreased with that of bacteria.