Marcus Valerius Maximianus was an important Roman general of the period of the Marcomannic Wars during the reign of Marcus Aurelius.

He is born (year unknown) in the Roman colony of Poetovio (modern Ptuj, in Slovenia), where his father, also called Marcus Valerius Maximianus, is local censor and priest.

He is decorated for services in the Parthian war of Lucius Verus and is appointed by Marcus Aurelius to ensure the armies in Pannonia are supplied by boats on the Danube.