The present study was undertaken with the objective to estimate the length-weight relationship of Puntius denisonii collected from five geographically separated rivers of the Western Ghats biodiversity Hotspot of India. A total of 281 specimens were sampled and measured from different rivers. The study resulted, the value of regression coefficient (b) in P. denisonii remained within the range of 2.97-3.19 with the median value was 3.11. Analysis of covariance revealed no significant difference (p<0.05) in the length- weight relation of P. denisonii in different rivers. These results indicated that populations of P. denisonii in the different rivers followed an isometric growth pattern with 'b' values did not varying significantly (p<0.05) from cubic value of 3.