The ancient city of Aizanoi is located in the Cavdarhisar district of Kutahya province. The city's first settlement dates from the Hellenistic period, and it retained its importance during the Byzantine period. Today, settled life may be found in the vicinity of the ancient city. The odeon of the city was built to the southeast of the Zeus Temple and is presently situated to the north of the residential area. The structure was originally built as a "bouleuterion" toward the end of the first century or the beginning of the second century A.D. It is thought that it was converted to an odeon in the fourth century A.D. by the addition of a stage structure. Archaeological excavations began in 1998 to uncover the remains of the building. During these excavations, which lasted until 2016, it was discovered that the building had undergone several interventions during the Byzantine period and was also seriously damaged by road construction works to reach the, resulting in settlement. The structure has expansions and repairs from different periods, as well as reused building materials. Experimental studies were conducted to determine the material properties of the building, with damage assessment studies carried out between 2017 and 2019. This article presents the data from the archaeological excavations the material properties of the different periods, the conservation problems, and the interventions made to bring the building to its current state.