Prune dwarf virus (PDV) isolates have been investigated for genetic diversity. Full-length nucleotide and amino acid sequences of viral coat protein from 23 isolates collected from different stone fruit trees (sour and sweet cherry trees, wild cherry tree, plum tree, almond tree, peach tree) and different countries (Poland, Italy, Germany, USA, Israel) were analysed and compared to 57 others available in GenBank. Comparison of all sequenced virus isolates revealed diversity of 86-100 % at nucleotide level and 79-100 % at amino acid level. The ratio of non-synonymous to synonymous polymorphic sites indicated that purifying selection dominated in case of PDV. However, six codons showed to be under strong positive selection, including the codon located inside the structure involved in RNAbinding activity.