The effects of iron (Fe) deficiency on fruit yield and quality were measured in two peach cultivars, Carson (yellow-skin fruit) and Babygold (red-skin fruit). In both cultivars, Fe deficiency caused major decreases in fruit fresh weight per tree and number of fruits per tree. Fruits from Fe-deficient peach trees had a smaller size, resulting in a large decrease in the percentage of commercially acceptable fruits, whereas fruit firmness was unaffected. In cv. Babygold, Fe deficiency greatly decreased the red color of the fruit skin. Part of these results was likely associated with a delay in fruit ripening. When fruits with similar appearance were compared, taking into account fruit size, color, and firmness, Fe deficiency generally led to higher concentrations of organic anions (especially succinate and quinate), vitamin C, and phenolic compounds and to lower total sugar/total organic acid ratios. This could lead to decreased fruit eating quality and to a slight improvement in fruit nutritional value.