Background: Although particulate matter likely provokes inflammatory reactions in those with chronic skin disorders like atopic dermatitis, no study has examined the relationship between particulate matter and psoriasis exacerbation. Objective: This study evaluated possible associations between particulate matter and hospital visits for psoriasis patients in 7 major cities in South Korea. Methods: We investigated the relationship between psoriasis and particulate matter. To do this, we used psoriasis patient data from the Korean National Health Insurance Service database. In addition, PM 10 and PM 2.5 concentration data spanning a 3-year time frame were obtained from the Korea Environment Corporation. Results: A pattern analysis generated by the sample cross-correlation function and time series regression showed a correlation between particulate matter concentration and the number of hospital visits by psoriasis patients. However, the prewhitening method, which minimizes the effects of other variables besides particulate matter, revealed no correlation between the two. Conclusion This study suggests that particulate matter has no impact on hospital visit frequency among psoriasis patients in South Korean urban areas.