A 2 by 4 factorial experiment was performed to investigate the influence of ascorbic acid and various dietary energy concentrations on bone development. Two groups of 12 broiler chickens were allocated to one of each of the following dietary treatments: Three energy levels of 13.804; 13.096 and 12.456 MJ ME/kg of a starter ration and 13.544; 12,967 and 12.309 MJ ME kg of a finisher diet in combination with 4 levels of supplementary ascorbic acid of 0, 250, 500 and 750 mg/kg of the diet. Production figures were measured over an 8 week period. Randomly selected groups of birds were slaughtered at 4, 6 and 8 weeks of age. During the first 4 week period. the higher levels of energy resulted in lower feed intake and a consequent improved food conversion efficiency was recorded over the entire 8 week period. No interpretation could be attached to the significant interaction between energy level and supplementary ascorbic acid on live mass at 8 weeks of age. The ash and calcium concentrations of the tibia increased with decreasing energy levels. Breaking strength, ash, calcium and nitrogen concentrations of the tibia increased with age. Supplementary ascorbic acid had no influence on bone development.