The effects of tillage systems on the incidence and severity of early leafspot of peanut (Arachis hypogaea L.) caused by Cercospora arachidicola were determined in three peanut cultivars during a four-year field study. Conventional and conservational tillage systems were utilized. In the conventional system, the land was tilled with a moldboard plow to a depth of approximately 25 cm, disked, and peanut seed were planted in soil with minimum plant residue. In the conservational system the existing winter cover crop, wheat (Triticum aestivum L.), was killed with a herbicide. Two methods of seedbed preparation were used (in-row tillage and band-tillage) in the conservational tillage systems. A 25-cm wide band was tilled with a modified rotary tiller in the band-tilled plots. In the in-row tilled plots, seed were planted directly into the killed winter wheat residue with minimal soil preparation. At the end of the growing season, leafspot incidence and severity were significantly less in 1984 and 1986 than in 1985 and 1987. Leaflet infection, precentage defoliation, and lesions per leaflet were significantly greater in conventional tilled plots than in band-tilled or in-row tilled plots. Disease incidence and severity were similar in band-tilled and in-row tilled plots. Pod yields were greater in conventional tilled plots than in band-tilled or in-row tilled plots.