Zooplankton samples were collected from the indigenous tropical brackish water lagoon during the wet monsoon (January and February 1990) and the dry monsoon (April and May 1990). The dominant copepod species in the zooplankton community comprising of Oithona sp (especially O. nana and O. robusta) accounted for more than 70% of the zooplankton in January and was gradually replaced by other zooplanktonic species later in the dry season. The lipid contents in zooplankton varied from 0.18 to 1.04% wet weight or 1.14 to 5.92% dry weight respectively. The major fatty acid contents of the zooplankton showed high concentration of 14:0, 16:0, 18:1, 20:5 omega 3 and 22:6 omega 3 especially in the wet season. It also contained high omega-3 highly unsaturated fatty acid series necessary for the growth of commercial fish larvae. It has a better food value than the normally use food organism, brine shrimp; thus reflecting its potential use as food organism for fish larval rearing.