An experiment was carried to study the effect of replacement of inorganic zinc with organic source on nutrient utilization and growth performance in buffalo heifers. Eighteen buffalo heifers (261.1±11.6 kg) were randomly divided in 3 groups of six animals each and were allotted to 3 dietary treatments, prepared by replacing the source of Zn supplementation (80 ppm) in concentrate mixture, i.e. Zn supplied from 100% ZnSO4 (100I–0O), 75% Zn from ZnSO4 and 25% from Zn proteinate (75I-25O), and 50% Zn from each source (50I-50O). Replacement of inorganic Zn with organic source had no significant effect on heifers body weight gain, feed intake and digestibility of day matter, organic matter, crude protein, crude fibre, ether extract, nitrogen free extract and fibre fractions in all the dietary groups. Thus, it was concluded that growth performance and nutrient digestibility were comparable among three dietary treatments irrespective of zinc source.