One hundred twenty Harco SL hens were fed diets varying in vitamin C supplementation (0, 100, 125 or 500 mg/kg feed) from 60 to 66 weeks of age. The main results can be summarized as follows: (a) The egg number was higher in hens of group C (0.78 eggs/hen/day). The hens of B and D groups had lower egg production than that of the control; all the differences were not statistically significant; (b) the feed consumption and feed ratio/egg dozen were better (P0.001) in hens of group C than in the control (differences 24.3 and 30.5%, respectively); (c) the livability was not affected by vitamin C; (d) the egg shape, shell deformation, shell thickness and shell weight were not affected by the supplementation of vitamin C, although egg shell quality values was numerically better in group C and (e) blood and meat spots of eggs laid by hens fed 500 mg vitamin C/kg feed was reduced by more than 50%.