The effects of zinc fertilization on ascorbic acid and mineral concentration of Katahdin potatoes were investigated over 2 yr. During the first year zinc sulfate (ZnSOJ was banded during planting at rates from 11.2 to 224 kg/ha in two locations in New York. During the second year ZnS04 was banded during planting at rates of 0, 22.4, 44.8 and 112 hg/ha at one of the locations. Ascorbic acid content of tubers was higher only with the 112 kg/ha ZnS04 treatment. Zinc fertilization resulted in higher Zn concentration in tubers during both years and at both locations. Zinc fertilization increased amounts of Ca, Mn, Cu, Al and Co but did not affect Cd content in potato tubers.