The Ashtamudi Estuary (Kerala, India) is a major source of short-neck clams (Paphia malabarica) that supports the livelihood of about 3,000 people. As the Ashtamudi short-neck clam fishery is India's first MSC certified fishery from November, 2014, continuous monitoring of physic-chemical parameters is very much essential. Present paper deals with the study of physicochemical parameters of water and sediment of two stations in Ashtamudi Estuary. Among the stations, monthly variations in the physical and chemical parameters such as temperature (23.7 to 31.2ºC), pH (6.8 to 9.2), Dissolved Oxygen (2.1 to 7.8 mg/L), Salinity (6.0 to 36 ‰), Ammonia (0.004 to 0.207 mg/L), Nitrite (0.0 to 0.009 mg/L), Nitrate (0.001 to 0.105 mg/L), Phosphate (0.00 to 0.07 mg/L), Total suspended solids (TSS) ( 19.2 to 208.4 mg/L), Particulate Inorganic Matter (PIM) (5.0 to 173.2 mg/L), Particulate Organic Matter (POM) (3.8 to 42.1 mg/L), Chlorophyll 'a' (0.3 to 20.8 mg/L), Chlorophyll 'b' (0.0 to 1.76 mg/L), Chlorophyll 'c' (0.0 to 2.85 mg/L), major elements of organic substance, namely, Nitrogen (0.01 to 0.17%),Carbon (0.4 to 3.4 %), hydrogen (0.04 to 0.67%), Sulphur (0.04 to 0.35%),organic carbon ( 0.1 - 1.0 %) and sediment texture were investigated. All the parameters were within permissible limits. Most of the months (7 months) in Stn I & II, soil texture was '' Loamy fine sand'', followed by sandy loam except in January month in station II, wherein texture was fine sand.