Eight kinds of sweet orange peels extracts were investigated to compare their antioxidant active ingredients and antioxidant capacity. The results showed that the highest level of the content of polyphenols, flavonoids, tannins and vitamin C were found in Mayang Bingtang sweet orange peel extracts, which reached 7.60 mg gallic acid equivalent (GAE)/per gram dried sample (g·m_d), 4.57 mg rutin equivalent (RE)/g·m_d, 17.90 tannin (TAE) mg/g·m_d, 17.86 mg vitamin c (VC)/g·m_d, respectively. Meanwhile, Mayang Bingtang orange peel also showed the highest ferric reducing power (81.50±0.93 μmol Trolox equivalent (TE)/g·m_d), and very high 1,1-diphenyl-2-trinitrophenylhydrazine (1,1-diphenyl)-2-picrylhydrazyl (DPPH) free radical scavenging capacity (15.77±0.64 μmol Trolox/g·m_d) and 2′- hydrazine-bis-3-ethylbenzothiazoline-6-sulfonic acid (2, 2′-azino- Bis(3-ethylbenzothiazoline-6-sulfonic acid), (ABTS) free radical scavenging ability (77.70±0.75 μmol Trolox/g·m_d). Spearman correlation analysis showed that the contents of polyphenols, flavonoids, tannins and vitamin C were significantly correlated with antioxidant activity. Five major flavonoids such as hesperidin, naringin, hesperetin, nobiletin and tangeretin in orange peel were identified by high performance liquid chromatography, and the highest content was hesperidin (2.63±0.21～4.65±0.33 mg/g·m_d). Principal component analysis and hierarchical cluster analysis results showed that the eight kinds of sweet oranges could be divided into three groups. The first group include Yongxing Bingtang orange (A), Hongjiang Bingtang orange (B), Mayang Bingtang orange (D) and Liuyang navel orange (H), and the second group include Shimen Bingtang orange (C) and Shimen navel orange (E), and the third group consisted of Mayang navel orange (F) and Shaoyang navel orange (G). Especially in the first group rich in polyphenols, flavonoids, tannins, vitamin C content and high FRAP and ABTS radical scavenging capacity. The antioxidants content and antioxidant activity of sweet orange peel can be used as an important index to distinguish sweet orange from different producing areas.