["Japanese Psychological Research, EarlyView. ", "\nAbstract\nAlexithymia is a trait characterized by deficits in emotion processing. The Perth Alexithymia Questionnaire (PAQ) is a popular alexithymia assessment tool that has established strong psychometrics across a range of countries and language versions, but to date, limited work has been done in Asian samples. Here, we introduce the first Japanese version of the PAQ and use it to explore the manifestations of alexithymia in the Japanese population. A total of 406 Japanese adults (210 women, 187 men, nine not indicated, mean age = 40.32 ± 9.63 years) completed an initial online survey, and 143 of these (143 participants: 72 men, 71 women; mean age: 41.02 ± 8.34 years) provided test–retest data at follow‐up. Confirmatory factor analysis indicated that the Japanese version of the PAQ had a theoretically congruent factor structure, corresponding to the intended five subscales, as well as support for a general alexithymia factor. Internal consistency and test–retest reliability were good. Relationships with other measures of alexithymia, emotion regulation, and psychopathology further supported its validity. Our findings support the multidimensional nature of the alexithymia construct in Japan, and highlight the PAQ as a valid and reliable measure of alexithymia in Japanese adults. The capacity of the PAQ to robustly assess all facets of alexithymia, and to do so across both negative and positive emotions, appears to make it an excellent option for alexithymia assessments.\n"]