[2] The generic name refers to Rozhdestvensky's hypothesis that Probactrosaurus would be the direct ancestor of Bactrosaurus, a notion now discarded.

In 2002 David B. Norman published a revision of the genus, in which he reported the holotype specimen of P. alashanicus, the back of a skull, had been lost after being dispatched from Moscow to Beijing.

[3] In 1997 Lü Junchang named a third species, Probactrosaurus mazongshanensis, based on holotype IVPP V.11333 found in 1992.

[4] Today, this form is seen as more closely related to Equijubus and Altirhinus rather than to P. gobiensis and is therefore commonly referred to as "Probactrosaurus" mazongshanensis.

[6] Probactrosauurus was lightly built, with relatively long and slender arms and hands and only a small thumb spike.