The Archeological Museum of Agrinio was founded with the generous funding of the Papastratos brothers and first opened in 1969. It is situated southeast from the city park and features a variety of exhibits from all the archeological sites of the Prefecture. The exhibits derive from different time periods, covering a time span from the Neolithic age to the Roman Empire.

In the courtyard of the museum there are numerous tombstones and two 2^nd century roman statues representing female bodies.  In the first chamber, visitors will see ceramics from Sauria (today the village of Palaiomanina) and vessels from the 4^th and 3^rd century B.C, as well as findings from the Neolithic age, including jewelry, semi-precious stones and other ornaments. Some of the most valuable findings in the museum derive from Mycenaean tombs of the ancient city of Ithoria. The characteristic red vessels of the classical age are impressive, as well as the 4^th century amphoras and the ceramic idols from Arsinoe, the modern village of Aggelokastro.

Among the museum highlights is the inscription of Athinodoros on the west wall of the first chamber, placed between two marvelous Hellenistic statues of Aphrodite and of a female body. The exhibit of the first chamber also features vessels from the proto-Geometric and Geometric era, from the 9^th and 8^th proto-Christian era. Some of the most interesting artifacts include the 9^th century copper tripod with a basin, preserved in an excellent condition, and the stupendous 2^nd century B.C tomb pillar of Kritolaos with wonderful ornaments, including the representation of infant Hercules killing the snakes.  There are also two unique tomb pillars of the 7^th century from Naupaktia, excellent samples of Greek tomb pillars.

The second chamber of the museum features a wide range of clay-made items, figurines, two wonderful hydrias and copper items of the Mycenaean era: axes, spears, mirrors, hooks, ect. On the wall there is a line of marble busts: the bust of Meleagros, armed Aphrodite, Eros, Hercules and other busts representing heroes, gods and goddesses. Among the busts, there is the spectacular marble gate of the Macedonian tomb of Kalydona.

Other fascinating exhibits of the museum of the second chamber include parts of the Alyzia memorials, dating back to the 2^nd century AD, the large tub from Kalydona and the clay bathtub of Toroivia, dating back to the 3^rd century B.C. The last two are not exhibited at the moment.