Jiangjunosaurus is a genus of herbivorous stegosaurian dinosaur from the Oxfordian-age (Upper Jurassic) Shishugou Formation of the Junggar Basin, Xinjiang, China.

[1] The type species, Jiangjunosaurus junggarensis, was named and described by Jia Chengkai, Catherine Foster, Xu Xing and James Clark in 2007.

The usual vertical ridges are present but weakly developed; the frontmost and rearmost teeth lack them completely.

[1] Of the neck vertebrae the second, the axis, has a neural spine or processus spinosus that is rectangular in side view, due to a higher than normal front edge.

From the fifth cervical vertebra onwards large depressions appear on the lower rear side of the vertebral body.

However, CAT-scans of the Jiangjunosaurus fossils revealed that the openings are not connected to inner air spaces and thus probably served as vein channels.

They are slightly taller than wide in side view, have an obtuse triangular top and a constricted base.

The bases are transversely thicker than the top sections, which show a pattern of fine diverging ridges.

Characters that are typically stegosaurid are the inclined quadrate; the vertical plate on the dentary; the depression on the pterygoid flange of the quadrate; the bottom edge of the scapula exceeding the upper edge of the coracoid in length; and the double row of larger neck plates.

A basal stegosaurid position is suggested by the horizontal front branch of the quadratojugal combined with a ventral process on the main body.