Allogynogenetic crucian carp was fed by purified diets containing different contents of crystalline ascorbic acid (AA) and coated ascorbic acid (CAA). Signs of ascorbate deficiency were not observed in fish fed ascorbate-free dict. The growth rate and the content of vitamin C in liver and serum were highest when diets contained 400ppm AA or 200ppm CAA. Thus, the requirement of Vc in diet for Allogynigenetic crucian carp being 400mg/kg is suggested.