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Abstract: Antioxidant activities (μmol Trolox equivalent (TE)/g fresh weight) of 19 sweet potato genotypes with distinctive flesh colour (white, cream, yellow, orange and purple) were measured by oxygen radical absorbance capacity (ORAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2′-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS). Total phenolics were measured using the Folin–Ciocalteau method, total anthocyanins by the pH-differential method, and β-carotene by HPLC. The total antioxidant activity (hydrophilic+lipophilic ORAC) was highest (27.2μmol TE/g fresh weight (fw)) for NC415 (purple-fleshed) and lowest (2.72μmol TE/g fw) for Xushu 18 (white-fleshed). The hydrophilic-ORAC values were significantly correlated with the DPPH (R 2 =0.859) and ABTS (R 2 =0.761) values. However, the lipophilic-ORAC values were poorly correlated with the β-carotene contents (R 2 =0.480). The total phenolic contents (0.011–0.949mg chlorogenic acid equivalent/g fw) were highly correlated with the hydrophilic-ORAC (R 2 =0.937) and DPPH (R 2 =0.820) values. Therefore, the total phenolic content can serve as a useful indicator for the antioxidant activities of sweet potatoes. [Copyright &y& Elsevier]