A total of 14 local potato cultivars were screened against late blight resistance under field conditions with no artificial inoculation. All the cultivars were genotyped with three Microsatellite markers (SSRs) linked to the genes governing late blight resistance viz., Rpi - blb1, Rpi - bt1, and R3a. The aim of the investigation was to identify late blight resistant cultivars from some local potato cultivars so that these resistant cultivars can be utilized in genetic enhancement programs as resistant varieties are an important component of disease management. Two cultivars namely, Deshi-1 and Deshi-2 had moderate resistance towards the late blight in field condition. The rest of the twelve cultivars were expressed susceptible reactions. Through genotyping a late blight resistant gene was identified and characterized in those cultivars showing resistant disease reaction as they expressed band for the R3a gene based primer.