The impact of different dietary levels of sodium bicarbonate (NaHCO 3) on nutrient intake, acid-base status, nitrogen balance and weight gain was examined in growing male buffalo (Bubalus bubalis) calves exposed to hot summer conditions. In a complete randomized block design 60 animals of similar age and weight were divided into five treatment groups of 12 per group. Five isonitrogenous and isoenergetic diets were formulated and randomly allocated to a treatment group. The control diet (0SB) contained no NaHCO 3 , while diets 4SB, 8SB, 12SB and 16SB contained 0.4, 0.8, 1.2 and 1.6% NaHCO 3 , respectively. An increase in nutrient intake was recorded with increasing dietary NaHCO 3 level while the reverse was true for nutrient digestibility. Calves fed the 12SB and 16SB diets had higher nitrogen retentions than those fed the 0SB and 4SB diets. Significant increases in blood pH, serum HCO 3 and urine pH were recorded with increasing NaHCO 3 levels, with the highest in calves receiving the 16SB diet. Calves fed the 14SB and 16SB diets gained more weight than those fed the 0SB and 4SB diets. These results indicate that the best nutrient intake, acid-base status, nitrogen retention and weight gain occurred in the calves receiving the diet containing 1.2% NaHCO 3 .