Background  Complementary and alternative medicine (CAM) is being increasingly used among Koreans with chronic dermatologic diseases, such as androgenetic alopecia (AGA), atopic dermatitis (AD) and psoriasis. Objective  To quantify the usage of CAM in Korean patients with AGA, AD or psoriasis, and to offer valid information for the physicians frequently encountering such disorders. Methods  Outpatients (n = 678) from three tertiary hospitals were investigated independently by constructed and self‐directed questionnaire. Results  Of the respondents, 62.1% (421/678) of the subjects reported current or previous use of CAM for their dermatologic conditions (AGA, 67.2%; AD, 68.9%; psoriasis, 46.6%). In AGA, topical applicants (50.2%) were most often used, followed by dietary therapy and health supplements. In AD, bath therapy (39.4%) was most often used, followed by oriental medicine and topical applicants. In psoriasis, oriental medicine (33.9%) was most frequently used, followed by bath therapy and health supplements. The proportion of patients who believed that CAM helped to improve their skin condition was relatively low (AGA, 16.1%; AD, 31.7%; psoriasis, 15.0%). Limitations  The results may not be applicable to other countries and generalized to general populations. Conclusion  These results indicate that CAM is widely used in Korean patients with chronic dermatological diseases despite their dissatisfactions. Thus, the advantages and disadvantages of CAM must be considered before its clinical practice.