The Porticus Octaviae (Portico of Octavia; Italian: Portico di Ottavia) is an ancient structure in Rome.
The structure was built by Augustus in the name of his sister, Octavia Minor, sometime after 27 BC, in place of the Porticus Metelli. The colonnaded walks of the portico enclosed the temples of Jupiter Stator and Juno Regina, next to the Theater of Marcellus. It burned in 80 AD and was restored, probably by Domitian, and again after a second fire in 203 AD by Septimius Severus and Caracalla. It was adorned with foreign marble and contained many famous works of art, enumerated in Pliny's Natural History. The structure was damaged by an earthquake in 442 AD, when two of the destroyed columns were replaced with an archway which still stands. The church of Sant'Angelo in Pescheria was built in the ruins circa 770 AD.
Besides the pre-existing temples, the enclosure included a library erected by Octavia in memory of her son Marcus Claudius Marcellus, the curia Octaviae, and a schola. Whether these were different parts of one building, or entirely different structures, is uncertain. It was probably in the curia that the senate is recorded as meeting. The whole is referred to by Pliny the Elder as Octaviae opera.
The portico was used as a fish market from the medieval period, and up to the end of 19th century. This role is remembered in the name of the annexed church of Sant'Angelo in Pescheria (Italian: "the Holy Angel in the Fish Market").
The building, which lies in rione Sant'Angelo, represents the center of the Roman Ghetto.