Silkworm Lepidopteran insect is of immense economic importance for the production of silk which is vulnerable to a various microorganisms resulting in crop losses to sericulture industry. It is infected by various disease viz., Pebrine (Fungal disease), Flecherie (Bacterial disease), Grasserie (Viral disease) and Muscardine (fungal disease). Among these, Pebrine is the most important disease of silkworm that is caused by Nosema spp. and is commonly observed in all the seasons but during the rainy and winter season, its infection level is more. It is a spore forming obligate intracellular microsporidia that causes the irresistible pebrine disease in silkworm which are transmitted by either horizontal and vertical or transovarial transmissions.