We investigated the acoustical characteristic of the sounds of crickets and its physiological and psychological effect on Japanese people. The sounds of crickets belonging to Family Grylloidae were grouped into 3 clusters by using the acoustical characteristics of the sounds. For this study, 3 Grylloidae species and 2 Tettigoniidae species were selected, and the sounds were recorded in a dark room. The psychological effect, i.e., pleasantness, was investigated by administering a questionnaire, which was based on the Semantic differential (SD) method. The comfort provided by the sounds was estimated on the basis of the findings on electroencephalograms in terms of an increase in the alpha wave. From the results of the questionnaire, people preferred the sound of crickets belonging to Family Grylloidae, rather than to those of crickets belonging to Family Tettigoniidae. It seemed that there was a deep relationship between the generation of alpha wave and the duration of the silent time within the sequential sounds. On the other hand, the rate of alpha wave increase in each species was not in good agreement with the results of the questionnaire, suggesting that further study is requires to understand the relationships between psychological and physiological effect on the human's Kansei. Finally, we proposed the effective presentation of the pleasant cricket sounds.