Abstract: Penicillium citrinum causes white muscardine in tasar silkworm and significantly damage cocoon production at farmer’s field. Four systemic fungicides Bavistin, a carbandazim fungicide (AK 1), Bayleton, a triazole compound (AK 2), Dithane M-45, a mancozeb fungicide (AK 3) and Thiram, a dimethyl dithiocarbamate (AK 4) were tested for efficacy to control white muscardine in, Antheraea mylitta D. One and two percent of AK 1 and AK 3, 0.15 to 2% of AK 2 and 2% of AK 4 in aqueous solution were found to be effective in in vitro condition for the control of muscardine. These fungicides on feeding through the T. arjuna leaves continuously for two days in 5th instar larvae inoculated topically with conidia of Penicillium citrinum (4x106 conidia mL-1) resulted in reduction in mortality due to muscardine by 49-94% as against 100% mortality in inoculated control (control 6). AK 1 reduced the mortality by 93 and 94% in the final instar silkworm at 1 and 2%, respectively. AK 2 at 0.05 and 0.1% concentration reduced the mortality by 85 and 87%, respectively. In case of AK 3 and AK 4 at 1% concentration reduced the mortality by 88 and 69%, whereas at 2% reduced mortality by 90 and 75%, respectively. No mortality was noticed in the controls 1 to 4 which indicated the non toxicity at the particular concentrations. Bavistin (AK 1) and Dithane M-45 (AKP 3) at 1 and 2% concentrations were more effective among tested systemic fungicides in suppressing muscardine in tasar silkworm.