Bombyx mori has long been reared as a beneficial insect in the sericulture industry and as an experimental laboratory insect. In tropical countries like India, grasserie, (BmNPV) spreads by the occultation bodies (OBs) in the blood cell of infected silkworm, usually high temperature and humidity prevalent in tropical regions is conductive to proliferation of polyhedrosis disease. It is known to occur in all larval instars during all seasons causing 20-50% cocoon crop losses in India. In the present study, four promising bivoltine hybrids will be screened for their susceptibility to BmNPV and BmIFV, Muscardine and other diseases and the susceptibility status has been compared across monsoon season of Uttar Pradesh. This will help in selecting most promising race for Autumn season of which will be least susceptibility to different Silkworm diseases viz., Grasserie, Bacterial flacherie, Muscardine and % other diseases (DNV, CPV, IFV, Sotto disease) and farmer will face less difficulty during silkworm rearing and will have no fear of attack of diseases. It will lead to further adoption and spread of Sericulture in other districts of Uttar Pradesh.