Bleaching powder solution (1 to $5\%$), slaked lime solution (0.1 to $0.5\%$) and formalin (1 and $2\%$) were tested for their efficacy against cytoplasmic polyhedrosis virus and Nosema mylittansis spores to control virosis and pebrine respectively in tasar silkworm, Antheraea mylitta in indoor rearing condition. All the disinfectants tested were found effective in suppressing the infection of virosis and pebrine significantly. Complete inactivation of Antheraea mylitta cytoplasmic polyhedrosis virus (AmCPV) was recorded when treated with $4\%$ bleaching powder, $0.4\%$ slaked lime for 20 min and $2.0\%$ formalin for 30 min. Similarly treatments of $3.0\%$ bleaching powder solution for 20 min and $2.0\%$ formalin for 30 min were found effective in complete inactivation of N. mylittanis spores.