Zuoyunlong (meaning "Zuoyun County dragon") is an extinct genus of herbivorous ornithischian dinosaur belonging to the Hadrosauroidea, that lived during the Late Cretaceous in the area of present China.

The generic name refers to the prefecture of Zuoyun with the Chinese word long, "dragon".

The descriptors established a unique feature derived, or autapomorphy for this taxon: the back sheet of the ilium has only half the length of the main body.

The shaft of the buttock ends in a side view in a large "foot" the tip of which points obliquely downwards and forwards.

[1] A cladistic analysis found that Zuoyunlong had a basal position in the Hadrosauroidea, as sister taxon of Probactrosaurus.