In this experiment utilization efficiency of mulberry silkworm was studied. Acetone extact of Annona muricata was evaluated on rearing performance, nutritional efficiency, commercial characters of silkworm in vitro (24₊1⁰, 75+5% RH and 16L:8D). In this study, the antibacterial activity of sour sap of five different solvents were evaluated using disk diffusion method against two colonies of bacteria (colony-1 and colony-2). The highest zone of inhibition (19.33mm) was observed with acetone leaf extract against both colonies. The efficiency of conversion of ingested food (ECI), conversion of digested food (ECD), digesta, approximate digestability (AD), reference ratio (RR) after treatment with A. muricata at T3 treatment was high when compared to other treatments and control which may be due to growth stimulation factors and also the presence of secondary metabolites. It can be concluded from above mentioned studies the silkworm feed on mulberry leaves fortified with A. muricata at different concentrations influenced the larval growth, nutritional efficiency and cocoon characters which are beneficial to the farmers.