Negombo lagoon is an estuarine ecosystem with an extern of 3502 ha under water, located in Attanagalu Oya basin. It is characterized with a large freshwater suppy from 932.4 square kilometer catchments area and restricted water exchange with the open ocean. The lagoon considerably choked in tidal amplitudes due to its narrow inlet. The lagoon is rich in biodiversity and also in fishing gear diversity. The gcomorphology of the lagoon, tidal exchange pattern, distribution pattern of the mangrove vegetation, extent of the inter-tidal area around the lagoon leads lo|a greater niche diversification within the lagoon. This leads to high faunal diversity resulting to high fishing gear diversity, fishing is the most important economic activity in the lagoon with over 10,000 people directly or indirectly dependent on fishing for their livelihood. Present study, which was carried out during January to December 2004, revealed the existence of 34 fishing practices qf which 17 were operated targeting juvenile and siib-jadult stages of Pcnaci J prawns. Cast nets, Gill nets, Stake seine nets, Brush piles, Trawl type of collecting nets. Trammel nets, Crab nets and Crab pots arc the important fishing gear types operated in the lagoon. Lagoon has four major ecological zones - Lagoon mouth, Lagoon proper, Transitional swamp and the. Marsh. A zonal distribution pattern was observed for certain fishing gear types. Although the transitional swamp is a small area whenjeompared to the other parts of the lagoon, it showed the highest fishing gear diversity.