The availability of prawn seeds in Kottaickarai, Uppar, Vaigai and Kottakkudy Estuaries were studied during 1986-87. The prawn seed survey was conducted by operating velon drag nets in different biotopes. Suitable site for the collections have also been investigated. Seeds of Penaeus indicus, Penaeus merguiensis, Metapenaeus monoceros, Metapenaeus dobsoni, Penaeus semisulcatus and Penaeus monodon were encountered in these estuaries in the order of abundance. Among these estuaries, Kottakkudy and Uppar have a rich potential for many culturable species of prawn seeds. Further information on the seasonal and spatial distribution pattern of the prawn seeds in relation to salinity and temperature are presented and discussed.