This paper dealt with estimation of catch fish demand function in Uttar Pradesh. Demand functions desirable therelationship between the quantity demanded and the various factors affecting the demand. Demand is determined by many factors simultaneously yet in traditional demand curve, the quantity demanded of a product is assumed to depend solely on price of product. Consumer survey was conducted for estimation of demand function of fish species. The total amount of fish consumed per day in kg. price of different fish species, income of the consumer house hold were collected from the market. When the preference for fish will increase by 1 unit the quantity demanded for fish was increased by 0.16 units. The result justifies that when price of substitute good increase the demand for main commodity increases. The result was also in accordance to when price of fish will increase, the demand for fish will go down. Similarly the preference pattern for fish also follows the economic logic. The similar pattern as the linear demand function, the explanatory variable like income, price of mutton, price of fish and preference for fish were found significant. Interestingly, the estimated co-efficient of price of fish was estimated to be -0.39, indicating there by when price of fish was increased by 1% he quantity demanded for fish was decreased by 0.39 percent. For this reason the estimated co-efficient of C-D demand function with respect to prices of fish will be used in computation of economic

surplus.