Exosomes are membranous nano-vesicles of endocytic origin that are released by almost all cell types and play an important role in cell-to-cell communication. Many researches have been carried out to illustrate the role of exosomes in the life cycle and pathogenesis of RNA viruses, however , information regarding their role in Bovine leukemia virus (BL V) is meagre. Herein we tried to investigate the role of exosomes isolated from plasma in BL V life cycle. Exosomal fractions were isolated from 18 fresh BL V-positive plasma samples by size exclusion chromatography (SEC) and then were tested using western blotting, RT -PCR and sequence analysis.Our results showed that absence of BL V enveloped protein (env) in all tested exosomal fractions, on the other hand around 22% of samples showed the presence of partial BL V RNA in their exosomes. From this approach, it was emphasized that the exosomes may incriminate in BL V pathogenesis through transfer of viral RNA from infected to uninfected B cells.