The present study was carried out to determine the water quality in terms of physicochemical parameters in the coastal waters of Thondi , Palk Bay for a period of one year from Jan2015  to Dec 2015. The analysis of different parameters such as temperature, pH, salinity, TDS, nitrite, nitrate, silicate, inorganic phosphate and total phosphate were carried out using standard methods. Water temperature ranged from 26.0°C-30.0°C, Salinity ranged  (30.1-34.55‰, pH(8.0 -8.2), EC value (45.20103mho- 50.49 103mho), Turbidity 28-59 NTU, TSS value (58.28-95 mg/l), DO (4.01 ml/l -5.61 ml/l), BOD (0.16 mg/- 2.19 mg/l), Chemical Oxygen Demand (0.87 ml/l -19.9mg/l ), Chloride 17252 mg/l -17850 mg/l ), Sulphate (1098.79 mg/l - 2637.41 mg/l),Nitrite  (0.117 µm/l and 1.192 µm/l), nitrate (1.513 µm/l and 12.981 µm/l), Ammonia (0.017 µm/l  and 0.11 µm/l), total nitrogen  (16.531 µm/l and 35.616 µm/l), inorganic phosphate (0.523 µm/l and maximum 2.047 µm/l), Total phosphorus (0.81 µm/l  and 4.386 µm/l)and silicate was recorded 41.676 µm/l and 61.149 µm/l.In sediment samples pH(7.7 -8.1),  Total Phosphorus(1.40µg/g -2.58 µg/g), total nitrogen (4.14 µg/g -9.80 µg/g), total organic carbon (1.70 mg/g-5.84 mg/g).The studies revealed that the physico-chemical parameters of water and samples showed  seasonal variations in Thondi coastal waters. Key words: Physico-chemical Parameters, Nutrients, statistical analysis, Palk Bay.