A study on the characteristics of the Spodoptera litura nucleopolyhredovirus (SpltNPV) was carried out. The result shows that the virus was pathogenic and specific to its host, S. litura larva. It caused 96% larval mortality within a period of 10 days at a dosage of 6 x 108 PIBs/larva and did not affect lepidopteran larvae, Spirama retorta Clerck (Noctuidae) and bagworm, Pteroma pendula Joannis (Psychidae). The polyhedra, varied in their shape, contained many virions with more than one nucleocapsid in a virion.