Viewing positions of autostereoscopic 3D affect the observed 3D image quality. The response of the people who had little experience in viewing autostereoscopic 3D was investigated. Thirty participants with the normal stereoscopic vision were selected and took the visual evaluation of autostereoscopic 3D at the various viewing positions. Photograph was also taken for the quantitative analysis of the viewing zone characteristics and the uniformity of 3D screen of autostereoscopic 3D. In visual evaluation, the larger difference of good and bad 3D image quality was observed at the viewing distance of 300 cm than at other viewing distance. This result and the periodic trends accorded with the analysis of photos at various camera positions. From these, we found that even the unexperienced viewer can correctly evaluate whether 3D image quality is good or bad.