To compare the fruit quality differences between the Sweet Orange (Citrus sinensis Osbeck) bud mutant “Hetaocheng (HTC)” and its wild type, the genetic relationship and fruit physiochemical properties were analyzed. The results prelimarily showed that “HTC” was a bud mutation of ‘Newhall’ navel orange, with a genetic similarity (based on the genome sequence speculation) as high as 96.6% and a similar phenology period. The average single fruit weight of “Hetaocheng” in the cultivation area of Wuhan was 90.11 g. which was significantly smaller than that of ‘Newhall’ (188.46 g), the soluble solids (TSS) was 10.63%, which was no difference from that of ‘Newhall’. The total carotenoid content of the peel of “HTC” was 309.96 ug/g DW, which was significantly lower than that of ‘Newhall’ (357.73 ug/g DW), and the total carotenoid content of the pulp was 31.57 ug/g DW, which was significantly higher than that of ‘Newhall’ (24.50 ug/g DW). And the contents of α-carotene, α-cryptoxanthin and lutein in the peel and pulp were significantly higher than that of ‘Newhall’. The above results indicated that the fruit size, peel hardness and carotenoid content in the peel bulged sweet orange mutant had all undergone significant changes compared with the wide type.