Nuclear polyhedrosis virus ofHelicoverpa armigera (HaNPV) from Madurai (south India) was isolated, purified and subjected to electron microscopical studies. The results indicate that the isolate is a multi embedded form of NPV. Further, STEM observations on polyhedra and polyhedral envelope of the HaMNPV are presented. The restriction pattern and genome size of HaMNPV Madurai isolate are compared with HaNPV isolates reported earlier. A dendrogram is presented to show the relatedness among the isolates.