Abstract This study aimed to evaluate the reliability and validity of the Japanese version of the Cultural Distance Questionnaire (CDQ), and to examine whether or not the measured cultural distance influenced the psychological adjustment of international exchange students and, if so, which aspects were most influential. Subjects were 211 Japanese high school and college students who stayed for one year with a host family in one of 23 countries around the world. They were asked to complete the Maudsley Personality Inventory before departure from Japan, the 12-item General Health Questionnaire six months after arrival in the host country and the CDQ six months after they returned from abroad. We found that the CDQ had high internal consistency reliability. Satisfactory validity was suggested for the CDQ because it offered wide coverage of various aspects of daily lives that reflect cultural differences, because it was uncontaminated by social desirability or by personality traits and because the obtained scores by country and region were largely in accordance with the expected directions. It was found that the greater the cultural distance between Japan and the foreign community, as measured by the CDQ, the greater the psychological distress of the international student placed in that community. Furthermore, the results showed that it was the food that had the greatest impact on the intercultural adjustment.