Kaatedocus is a flagellicaudatan sauropod genus that originates from the mid-Late Jurassic period, specifically during the Kimmeridgian stage, in northern Wyoming, United States. This dinosaur is identified through well-preserved skull and cervical vertebrae fossils recovered from the lower part of the Morrison Formation.

In comparison to most diplodocids, Kaatedocus was relatively smaller in size. The estimated length of the type individual is approximately 14 meters (46 feet), with the combined length of its skull and neck reaching around 3.8 meters (12 feet). The neck comprised at least 14 vertebrae, a number consistent with the typical count seen in diplodocids.

Initially, in 1934, fossils attributed to Kaatedocus were unearthed and assigned to the Barosaurus genus. However, subsequent examination of these fossils revealed that they indeed represent a distinct genus within the diplodocid sauropod family.