Blue Tongue (BT) is a non-contagious, arthropod-borne viral hemorrhagic disease of domestic and wild ruminants and camelids with no known zoonotic potential. It clinically affects sheep, but other ruminants as cattle, buffaloes, goats and camels act as asymptomatic silent carriers. Therefore present dissertation has been proposed to study the genetic variation among the BTV serotype 2 isolates in Andhra Pradesh: 1.To amplify full length of VP2 and VP5 gene by RT-PCR. 2.To characterize and sequence the amplified product of VP2 and VP5 genes. 3.To make phylogenetic analysis of VP2 and VP5 genes of BTV serotype 2.