Recently, public and commercial firms are constructing their own concert hall specialized for classical music, as level of public life rises, and spare time for leisure increases after introducing a five day workweek. As classical music become more familiar than past, and people are strongly attracted to a cultural experience. Obviously, the most important factor of these concert halls is an acoustic ability of the space. Therefore, a physical evaluation is compulsory. However, in domestic cases, most evaluations are done under the condition of vacant seats without an existence of audience. Therefore in this study, the evaluation was done under conditions of both vacant seats and fully seated, and difference between each result was analyzed. The result indicates that reverberation time and Early Decay Time were affected by audiences' rate of sound absorption in a large scale. Moreover, Bass Ratio was measured in relatively low value in vacant seats, however, when the hall was fully seated, the measurement increased by the sound absorption of human body. For the future evaluation in fully seated condition, audience should be informed carefully to prevent any possible human errors, as well as numerous mock-up tests are required. A purpose of this study is to be a baseline for any future physical acoustic experiment in seated condition.