Surfactants are amphiphilic compounds that reduce surface and interfacial tensions by accumulating at the interface between two immiscible fluids. Biosurfactants have been increasingly attracting the attention of the scientific community as promising candidates for the replacement of a number of synthetic surfactants by way of maintaining the cost of the raw material in its production process at a minimum. Renewable substrates from various sources, particularly from well-known industrial wastes can be utilized for the production of biosurfactants. The wastewaters generated from dairy industries contain large amount of fats and oils that makes such wastewaters not easily biodegradable. Utilization of dairy wastewater by microorganisms for the production of valuable bioproduct can solve both purposes: pretreatment of the wastewater and cost reduction in the bioproduct production process. Towards this goal, synthetic dairy wastewaters (SDWW) were prepared in our laboratory and tested for SLs production by the yeast Starmerella bombicola. The extracted sophorolipids were tested for its antimicrobial activity against the bacterial culters.The results states that the zone formation showed that the pathogens like E.coli, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa were sensitive to sophorolipid and Vibrio cholerae was resistant for both crude and dialysed sophorolipid.