The book presets a detail account of algae of Chilika Lake, the largest brackish water lagoon in Asia, in the East coast of India. The algal forms of the lake were collected during the year 1999 to 2001, documented with microphotograph and camera lucida diagrams and identified by us. The taxonomic account of these algal forms has also been prepared. Besides the documentation of algal forms, resource mapping and biomass estimation of economically important algal species in different salinity gradients of the lake was carried out for the first time and presented in this book. Viable protocol for agar-agar extraction from Gracilaria verrucosa occurring in the lake and its possible commercial exploitation is also given. Details of algal forms presented in this book with descriptions, photographs, line diagrams and site of occurrence in Chilika lake can be used as a monograph for future study of algal diversity changes in Chilika lake and other wetlands elsewhere. Contents Chapter 1: Chilika Lake and its Biodiversity; General features of Chilika lake, Origin and history of the lagoon, Importance of Chilika lake, Chilika lake as a Ramsar site, Hydrology and water quality, Climate, Problems encountered by the lake, Biodiversity of Chilika lake, Biodiversity of marine algae in the brackish water lakes, estuaries and coastal regions of India; Chapter 2: Algal Flora of Chilika Lake; The study sites, Collection, observation and identification, Systematic account of algae of Chilika lake; Chapter 3: Algal Biomass of Chilika Lake at Different Salinity Gradient; Physico-chemical characteristics of water, Biomass of macro-algae of Chilika lake, Biomass of phytoplankton of Chilika lake; Chapter 4: Agar Yield of Gracilaria verrucosa at Different Salinity Gradients of Chilika Lake, Pre-treatment of the material, Extraction of agar, Yield of agar, Gelling temperature, Melting temperature, Gel strength, Estimation of 3,6-anhydrogalactose, Estimation of sulphate contents in agar.