Processing of viral polyproteins of Bovine Viral Diarrhoea Virus (BVDV) by cellular and virus-encoded proteases gives rise to at least 11 structural and nonstructural proteins having molecular weights of 165, 125, 110, 93, 80, 70, 62, 53, 48, 44, 34 and 23 kDa. Some studies showed a small changes in molecular weight or number of the viral proteins. (Donis and Dubovi 1987). Cytopathic (CP) strains of BVDV expressing of NS3 (P80) and non-cytopathic (NCP) strains express the fusion protein NS2/3 (P125), but not NS3 (Qu et al., 2001), while in CP strains both NS2/NS3 and a discrete NS3 are observed (Agapov et al:, 2004, Balint et al., 2004). Proteinal pattern of various pestiviruses can be variable in different isolates and cleavage of viral proteins by viral and/or cellular proteases, would result in diversity in viral proteins (Becher et al., 196; Paton, 1995). ; http://www.mendeley.com/research/antigenic-pattern-bvd-viruses-isolated-iran/ ; F. Hemmatzadeh, H. Momtaz, H. Keyvanfar and E. Banihasan