This study was performed on 302 cases of leptospirosis, tsutsugamushi disease and hemorrhagic fever with renal syndrome(HFRS) which occurred in Chonnam(Do) in 1991 through 1993. The results were as follows : 1. 81.8% of the patients with Leptospirosis and 54.5% of the HFRS patients were men while 61.4% of the patients with tsutsugamushi disease were women. 2. Most patients lived in rural areas(Gun), their educational level was elementary School or lower and their occupations were either farmer or jobless. 3. Peak ages were 40s for leptospirosis(36.4%) and 50s for tsutsugamushi disease and HFRS(32.9% and 36.4% respectively). 4. The high incidence areas of tsutsugamushi disease were northern, eastern and a diagonal line, from northeast to southwest, of the Chonnam area, and these are consistent with a mountainous district. 5. In monthly distribution leptospirosis was higher in Sep. and Oct., and tsutsugamushi disease and HFRS were higher in Oct. and Nov. 6. The first case is occurring and the last case shows up later than in past years.