Zooplankton samples collected during the cruises of M.V. Matsya Vigyani from October to December 1977 from the northwest cost of India were utilised for the study of the faunal composition, variation in their abundance, distribution and their relationship with the fishery. Estimated zooplankton biomass in the area 20-71 followed by 20-70 and this was due to a higher density of Salps spp. where they out numbered the copepods. Copepods were dominant in the areas 18-72 (98%), 17-72 (87.5%), 19-71 (80.7%) and 17.72 (55.6/0. Evadne sp. (39%) was next to copepods in the samples collected in the area 17-72 south of Bombay The percentage composition of various groups of zooplankton in different areas is given. The fish catch/hour was maximum in the area 19-71 (366.7 kg/b) followed by the area 18-72 (354.8 kg/h) in October which was the most productive month for the zooplankters.