Assessment of antibacterial as well as antiherpes virus activity of sulfonoquinovosyldiacylglyceride (SQDG), a glycolipid, isolated from the leaves of Azadirachta indica has been described. Antimicrobial activity was evaluated against Gram-positive, Gram-negative bacteria and herpes simplex virus. SQDG showed significant inhibitory activity against Salmonella typhi and two isolates of Shigella dysenteriae with MIC values 32gml(-1), while three isolates of Salm.typhi, Escherichia coli and Vibrio cholerae were inhibited at 64gml(-1) and have shown zone diameter ranging from 62 to 123mm. The growth kinetics study of SQDG on Salm.typhi and Sh.dysenteriae revealed that the growths were completely inhibited at their MIC values within 24h of exposure. Interestingly, SQDG inhibits herpes simplex virus (HSV) type 1 and 2 with the EC50 of 91 and 85gml(-1), compared with acyclovir (22 and 28gml(-1) against HSV-1 and HSV-2). The selectivity index (SI) was found to be 124 against HSV-1 and 1341 with HSV-2. Furthermore, the expression of proinflammatory cytokines of HSV-infected and SQDG-treated macrophages using ELISA kit revealed that SQDG significantly downregulated the production of TNF-, IL-1, IL-12 and IL-6.