The experiment was conducted at Holetta Agricultural Research Center and on-farm at Tikur Enchini during the 2017 main season to assess efficacy of alternate fungicides application and potato varieties on late blight epidemics. Treatments were factorial arranged in a randomized complete block design with three replications. Analysis was performed combined for the two locations due to homogeneous error variances. Combined analysis of variance indicated that effect of varieties, fungicide, locations and their interactions significantly reduced Late blight epidemic parameters and enhanced yield. The lowest mean AUDPC values (168, 291.15 and 456.5-%unit-days) were recorded on plots sprayed with Trust-Cymocop 439.5 WP +Ridomil Gold MZ 68 WG + Mancozeb 80 WP (TRM) spray sequence on the varieties Belete, Gudenie and Jalenie, respectively. High disease epidemics (AUDPC values of 1135.35, 963.35 and 1965.85- %unit-days) occurred on unsprayed plots of the varieties Belete, Gudenie and Jalenie, respectively. Alternate fungicide application with TRM spray sequence reduced late blight severity up to 75%, 60.84% and 68.33% on the varieties Belete, Gudenie and Jalenie, respectively, compared to the control. The overall results revealed that alternate fungicide application with TRM spray sequence are found effective to slow down potato late blight epidemics and improve potato productivity; and thus, recommended for the study areas along with other crop management practices.