Studies on different blood parameters were made in relation to body weight, locality and sex in Channa punctatus (Bloch.) and C. gachua (Ham). The RBC count, Hb content, WBC count and PVC increases with the increase in body weight by a fractional power of 0.16, 0.16, 0.30 and 0.57 (regression coefficient) respectively in C. punctatus. The correlation coefficients were high, ranging from 0.93 to 1.0. No statistical relationship could be obtained between the body weight and different blood parameters in C. gachua. Significant difference was found in different blood parameters in C. punctatus collected from two different localities. The blood parameters in males and female in the two species did not differ significantly.