Marine yeasts (33 strains) were isolated from the coastal and offshore waters off Cochin. The isolates were identified and then characterized for the utilization of starch, gelatin, lipid cellulose, ui ea, pectin, lignin, chitin and prawn-shell waste. Most of the isolates were Candida species. Based oi I rile biochemical characterization, foul potential strains were selected and their optimum pH and NaCl concentration for growth were determined. These strains were then inoculated into prawn-shell waste and SCP (single cell protein) generation was noted in terms of the increase in protein content of the final product.