The Aerarium ( from the Latin aes, bronze ') was the ancient Roman treasury. Your full name was Aerarium populi Romani (, treasure of the Roman people '). It was located in the Roman Temple of Saturn in the Forum, and was therefore also called aerarium Saturn.

The Aerarium was administered by two quaestors and was under constant supervision of the Roman Senate. It consisted of precious metals, money, field signs, certificates and bonds. At the same time it also served as an archive of public documents (eg Philinos Treaty). The Aerarium fed on taxes, revenues from leasing, fines and war booty.

In imperial times, the importance of Aerarium Saturni decreased as the imperial treasury, the fiscus, Augustus part of the revenue received that had been granted to the Aerarium. The administration went more and more into the hands of the imperial officer.

The founded by Augustus Aerarium militare, received their supply from the veterans who came in the course of the imperial period also increasingly under imperial control.

As Aerarium the public purse could be described by cities in the Roman Empire.