Background: Cleanroom air is extremely dry, as it is maintained within 1 % of relative humidity. Few studies have assessed the dermatologic life quality of workers in ultralow-humidity environments. Therefore, we aimed to evaluate the dermatologic life quality of cleanroom workers using the Skindex-29, compared to those of noncleanroom workers. Methods: Study participants were 501 cleanroom workers and 157 non-cleanroom workers from a secondary battery factory, who underwent an employee health examination at a single university hospital from September 2014 to September 2015. Results of the self-administered Skindex-29, and McMonnies questionnaire were analyzed. Other information and disease history were also collected during physician's medical examination. Descriptive and multivariate logistic regression analysis were performed. Results: The Skindex-29 score was significantly higher in cleanroom workers than in non-cleanroom workers for all domains, Symptom (16.0 ± 15.9