Abstract: Potato glycoalkaloids α-chaconine and α-solanine, the acid-hydrolysis products β1-chaconine, β2-chaconine, γ-chaconine and β2-solanine, and the 6-O-sulfated products 6-O-sulfated chaconine and 6-O-disulfated solanine was examined for their percent inhibition on radial growth of fungi using an agar dilution method, and then, the structure-antifungal activity relationships of them was analyzed. Results indicated that the nature, order and number of attachment of the carbohydrate residues of potato glycoalkaloids could strongly influence the antifungal activity.