Abstract: The Cirrhina mrigala the Munj Sagar Talab Dhar was studied for its weight-length relationship for the period of Nov. 2006 to Oct. 2008. Length-Weight Relationship (LWR) is useful in Cirrhina mrigala was 2.869. Statistical method such as co-relation, smoothing of data, regression and cluster analysis and polynomial curve fitting are helpful in predicting and planning of the ecosystem. The second order polynomial was found to be a best fit for LWR in present study.