This paper discusses the stimulation of the subject's strong emotion in listening music and the relationships between the impression or the strong emotion and acoustic feature values. Impressions of music are classified into five types: "charity," "nobility," "nostalgia," "passion," and "joy." First, using fifteen classical music pieces, an impression evaluation experiment is conducted to get the degrees of impression and strong emotion, and others, of the music pieces. Second, the acoustic feature values of the music pieces are extracted. The experimental results are compared with the acoustic feature values. As the result, it is proved that the acoustic feature values are related to the impression of music and the strong emotion. Also, it is suggested that it may be possible to estimate the impression of music by acoustic feature values.