| Xingxiulong Temporal range: Early Jurassic,
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| Photographs of skeletal elements (a-n) and skeletal reconstruction (o) of Xingxiulong chengi | |
Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Dinosauria |
| Clade: | Saurischia |
| Clade: | †Sauropodomorpha |
| Clade: | †Massopoda |
| Genus: | †Xingxiulong Wang et al., 2017 |
| Type species | |
| †Xingxiulong chengi Wang et al., 2017
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| Other species | |
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Xingxiulong (meaning "Xingxiu Bridge dragon") is a genus of bipedal massopodan sauropodomorph from the Early Jurassic of China. It contains two species; the type species is X. chengi, described by Wang et al. in 2017 from three specimens, two adults and an immature individual, that collectively constitute a mostly complete skeleton. Adults of this species measured 4–5 metres (13–16 ft) long and 1–1.5 metres (3.3–4.9 ft) tall. A second species, X. yueorum, was described by Chen et al. in 2025 based on a partial articulated postcranial skeleton of an adult individual larger than X. chengi. Phylogenetic analysis suggests that Xingxiulong is most closely related to its contemporary Jingshanosaurus, although an alternative position outside of both the Sauropodiformes and Massospondylidae is also plausible.
Despite their close relationship, Xingxiulong prominently differs from Jingshanosaurus—and from most basal sauropodomorphs—in having a number of sauropod-like traits. These include a sacrum containing four vertebrae; a pubis with an exceptionally long top portion; and the femur, the first and fifth metatarsals on the foot, and the scapula being wide and robust. These probably represent adaptations to supporting high body weight, in particular a large gut. Unlike sauropods, however, Xingxiulong may have still been bipedal.