Citrus yellow mosaic virus (CYMV) is a double stranded rod shaped DNA virus of genus Badnavirus, family Caulimoviridae. It's complete genome has been sequenced and characterized by Hang et al.,(2001). It comprises of six putative open reading frames and an intergenic sequence all lying on the plus strand of DNA and each capable of encoding proteins with a molecular mass of greater than 10 kDa. ORF 3, the largest ORF, encodes a putative polyprotein for functions involved in virus movement, assembly and replication. The other ORFs encode proteins whose exact functions are not completely understood. The genome also contains a plant tRNAmet binding site, which may serve as a primer for minus-strand DNA synthesis, in its intergenic region.It is responsible for a significant loss in Citrus crop in India.