Abstract An experimental study was conducted to observe the efficacy of different supplementary formulated diets on growth of Heteropneustes fossilis in terms of length-weight relationship and condition factor for 150 days. Four diets (Control - D1; Experimental - D2 - D4) were prepared by using plant protein sources i.e. soybean meal and groundnut meal in addition to traditional feed components i.e. rice bran and mustard meal of control diet. Significantly higher (p<0.05) average final body weight (23.92g) and specific growth rate (0.66) was recorded with diet D2 having major contribution from the soybean meal (24% rice bran, 24% mustard cake, 50% soybean meal). Maximum value of exponential ‘b’ (2.73), correlation coefficient ‘r’ (0.8510) and condition factor ‘K’ (0.67) in the diet D2 further showed the positive effect of soybean meal on fish growth. However, the range of exponential ‘b’ from 1.99 to 2.73 and condition factor ‘K’ from 0.59 - 0.67 in all the diets indicate robustness or well being of fish throughout the study period. Thus, the results of the study showed the acceptability of soybean meal by H. fossilis in terms of higher growth and condition factor.