The six major ginsenosides, Rg1, Re, Rb1, Rc, Rb2, and Rd, in roots and leaves of American ginseng have been isolated and quantified by high-performance liquid chromatography. In 4-year-old roots, the main ginsenosides were Re and Rb1, and together they accounted for >75% of the total ginsenosides. In leaves, the concentration and composition of ginsenosides varied with the maturity of the leaf tissue. One-month-old leaves contained 1.33−2.64 g ginsenoside/100 g dry weight, and the ginsenoside Re accounted for >50% of the total concentration. In mature, 4-month-old leaves, the total ginsenoside content ranged from 4.14 to 5.58 g/100 g dry weight, and the ginsenosides Re and Rd each accounted for ∼40% of the total ginsenosides. The production site of ginseng influenced the ginsenoside contents of roots and leaves. However, few significant correlations were found between root and leaf ginsenosides and between ginsenoside levels and mineral composition of the leaves and soil. Keywords: Panax quinquefolium; saponins; ginsenosides; HPLC analysis; soil fertility; leaf tissue nutrient status