Measurements of suspended carbon, carbohydrate, ninhydrin-positive nitrogen, and phosphate phosphorus were made from surface to bottom along a line of 14 stations from 32� 00'S., 111� 45'E. to 9� 00'S., 105� 00'E. The first three properties showed minima at 200 m and 1300 m. The minimum at 200 m was associated with horizontal advection of oligotrophic South-east Indian High Salinity Water. The minimum at 1300 m coincided with the boundary between the intermediate and deep circulation systems. No systematic change in composition of the suspended matter with depth was observed.