Two new isolates of cricket paralysis virus, TAR and SIM, are described that were originally isolated from laboratory colonies of Drosophila melanogaster and Drosophila simulans respectively. Using a combination of biological, serological and molecular characters it was possible to distinguish the SIM isolate from all other isolates and it is thus described as a new strain; CrPVSIM. The TAR isolate however, was indistinguishable from the CrPV reference isolate CrPVVIC/GM/D2(2)/Gm/D2(2) (Teleogryllus commodus, Victoria, Australia, 1968). The molecular characters used in the present study were obtained by combining PCR and restriction endonuclease digestion of the amplified fragments. This work demonstrates that such molecular characters, when used in combination with others, provide a powerful set of taxonomic characters for classifying CrPV isolates and strains and assessing their genetic relatedness.