Xingxiulong chengi was discovered in 2013, and was described in 2017 by Wang Ya-Ming, You Hai-Lu, and Wang Tao.
In 2013 the specimen was discovered in Sankeshu Village in Lufeng County, Yunnan Province, China. The specimen consists of three separate skeletons of the same species, one holotype and two paratypes.
Xingxiulong chengi is a basal sauropodiform from the Lufeng Formation. The dark purple rocks the specimens were found in correspond to the Hettangian age of the Early Jurassic.
The holotype consists of a partial skull and mandible, a number of vertebrae, rib fragments, left ilium, left pubic apron, partial right pubis, both femurs, both fibia, and both partial fibula, some tarsals, complete left foot, and mostly complete right foot. The holotype is estimated to be between four and five metres in length.
Paratype one consists of several vertebrae, rib fragments, the right scapula, right ilium, partial right pubis, partial femurs, and a partial left tibia. This paratype is estimated to be smaller than the holotype, at around 3.5 - 4.5 metres in length.
Paratype two consists of a partial skull with mandible, several vertebrae, rib fragments, both scapula, both sets of humerus, ulna, and radius, partial hands, right ilium, partial left ilium, left pubis, right pubic apron, broken left femur, right tibia and fibula, partial left tibia and fibula, broken toes, and a partial foot. The length pf paratype two is thought to be the same as the holotype, four to five metres.
Comparisons to other sauropodiformes suggests that Xingxiulong chengi is a more basal Massopoda and Sauropodiform, but it does have features that are normally present in Sauropods, the more advanced lineage of this evolutionary line, mostly supporting structures for supporting a large gut and high body weight. Being bipedal though, Xingxuilong is still a basal sauropodoform.
As with other sauropodiformes, Xinxuilong is herbivorous. This can be seen from its teeth and mandibles, as well as the body structure that support a large gut for digestion of vegetation.
"Xingxuilong" comes from Chinese; "Xingxiu" meaning "constellation". That part of the name was chosen from Xingxiu Bridge, a bridge in Lufeng County that was built during the Ming dynasty (somewhere between 1368 and 1644). "Long" is Chinese for "dragon", which is the name typically used for Chinese dinosaurs in place of the Latin "saur". "Chengi" is to honour Professor Zheng-Wu Chen, for his contributions to Chinese biostratigraphy in Lufeng County.