Seasonal distribution of chigger mites in the Kangwha Island and Yongjong Island was studied during the period of October 1992-August 1993. From 42 field rodents collected, 1,290 chiggers were obtained and 8 species of 4 genera were identified. In the Kanghwa Island, Leptotrombidium pallidum was the predominant species through all seasons with the percentage of 93.0%. Whereas, in the Yongjong Island, L. palpale was the predominant species with the percentage of 38.4% and L. pallidum was not found.