Four indigenous Japanese concepts of private life, secrecy, solitude and freedom were rated on 11 five-point bipolar adjective scales with the foreign concept of privacy by 131 Japanese male and female undergraduates. Factor analyses were carried out for each concept by using correlation coefficients among these scales. In addition, factor analysis was performed by using correlation coefficients among the concepts. Similarity rating data was also obtained for pairs of the concepts on a five-point scale. According to this data, private life and to a less extent, secrecy, were judged to be relatively more similar to privacy than the other concepts. Regarding factor structure, three Japanese concepts and, to a lesser degree, freedom were similar to privacy. In addition, all the concepts had significant and positive loadings on Factor I which was interpreted as privacy concept. Therefore, although private life and secrecy seemed to be relatively more similar to privacy, all the Japanese indigenous concepts were more or less associated with the concept of privacy.