Fewer stem lesions caused by Cercosporidium personatum (Berk. & Curt.) Deighton developed on peanut (Arachis hypogaea L.) cultivar Southern Runner than on cultivar Florunner in field tests conducted near Tifton, GA, in 1989 and 1990 and near Marianna, FL in 1990. Numbers of lesions per stem and lesions per dm of stem length ranged from 3.1 to 9.5 times higher on Florunner than on Southern Runner in tests where severe leafspot epidemics developed and no foliar fungicides were applied. Seven applications of chlorothalonil at 0.5, 0.63 or 1.26 kg ai/ha via ground sprays and 1.26 kg ai/ha via an underslung boom (Pivot Agricultural Spray System = PASS) allowed few stem lesions to develop on either cultivar compared to non-sprayed plants. Delayed harvest required for Southern Runner resulted in an increase in incidence of stem lesions, but incidence of stem lesions at harvest on Southern Runner still was significantly lower (P ≤ 0.01) than incidence on Florunner at harvest. Differences in number of stem lesions between the two cultivars and among fungicide treatments were reflected in yields. Healthier stem tissue due to fewer stem lesions may be partially responsible for higher yields in Southern Runner than in Florunner grown during severe leafspot epidemics. Incidence of stem lesions caused by C. personatum may be useful as a new parameter to be considered in evaluation and selection for resistance and/or tolerance to C. personatum in peanut.