The biological value of giant grasshopper protein ( Zonocerus variegatus
) was evaluated by comparing the weight gained, food efficiency ratio (FER), protein efficiency ratio (PER) of rats fed standard laboratory chow with that of rats fed giant grasshopper, Soyabean(Glycine max) and crayfish. The effect of high fibre content on utilization of nutrients has also been assessed in rats fed the supplements. Each diet produced a progressive gain in body weight ranging from 32.1 ± 2.0g in rats feeding on control diet to 56.0 ± 2.0g for rats feeding on giant grass-hopper. FER ranges between 0.22 in rats fed on laboratory chow to 0.44 in giant grass-hopper fed rats while PER ranges between 1.12 in laboratory chow fed rats to 1.90 in rats fed giant grass-hopper. Despite the fact that food and protein intake of rats on control and experimental diets were identical, at the end of the 28 day feeding period, the growth rate, FER and PER of giant grass-hopper fed rats were significantly higher (P < 0.05) compared with rats fed on Soyabean(Glycine max), laboratory chow and crayfish supplemented diets, thus suggesting that the giant grass-hopper protein was superior in terms of quality and was better utilized. The fiber content in giant grass-hopper was 15%, which was thrice the amount present in laboratory chow and one and half times the amount present in crayfish. Plasma levels of total protein, essential amino acids and minerals in rats on different diets were almost identical. This seems to suggest that the high fiber content in giant grass-hopper did not seem to affect the bioavailability and levels of these parameters determined in the plasma especially the total protein and minerals. The significant increase in body weight, the high values of FER and PER together with ease of collection(possibility of cultivation) and economic aspect would make giant grasshopper a suitable alternative, digestible and highly nutritive protein and its inclusion in food supplementation would provide good quality protein especially in developing countries. Additionally, giant grasshopper protein may also be included in animal feed formulation.