Abstract Computer modeling and earthquake simulation of historic structures and monuments is important for understanding their behavior and for predicting their response for preservation and strengthening studies. This paper focuses on analytical and experimental studies conducted on the historic Aspendos theatre, which is a 2200-year-old structure located in Antalya, Turkey. Concerts and performances are still presented at the Aspendos theatre and the recent usage of high decibel amplifiers during concerts generates an increasing amount of concern about the structural safety of the theatre. A detailed 3D-FE model and on-site dynamic acceleration measurements were used to evaluate seismic performance by response-spectrum and time-history analyses. The same model was utilized to evaluate the resonance conditions of slender and lightly damped theatre walls under sound-induced vibrations by equivalent static loading. The maximum tensile stresses calculated for the earthquake loading were several times the assumed tensile capacity of the material and dead load generated compressive stresses, especially at the base and upper corners of the walls. The building is expected to experience heavy structural damage during a possible large earthquake and it may be assumed that the theatre must have been repaired many times during its lifetime. Sound-induced resonance state stresses were relatively less critical but might still pose danger under rare and unfavorable conditions. Vertical reinforcement placement inside the slender walls would improve the out-of-bending capacity while connecting inner and outer walls by two levels of slab would enhance load transfer mechanisms to the perpendicular side walls and improve the theatre’s structural performance.