Abstract: Ten interspecific F1 hybrids were studied for the expression of heterosis in some productive parameters like bolls per plant, seedcotton yield per plant (gm), boll weight (gm), seed index (gm), ginning outturn (%) and staple length (mm). The range of mid parent and better parent positive heterosis respectively varied from 12.0 to 118.0% and 11.0 to 109.0% in the bolls per plant, 2.0 to 118% and 5.0 to 98.0% in seedcotton yield; 0.0 to 10% and 0.0% in boll weight; 1.0 to 26.0 and 9.0 to 26.0% in seed index; 1.0 to 4.87% and 1.15 to 4.87% in ginning outturn % and 0.0 to 11.32% and 0.32% to 5.33% in staple length. Considerable amount of heterosis manifested by various characters suggested possibility of more improvement in these characters, nevertheless higher magnitude of heterosis in number of bolls and simultaneous increase in yield further suggested that bolls per plant may be an important selection criterion for increasing cotton yield.