This study aimed to investigate the regional variations in the prevalence of late-stage chronic kidney diseases (CKD) in middle-aged and elderly population among the 18 townships in Chiayi County. We identified participants using the results of a community-based medical screening survey obtained from the computerized database of the Public Health Bureau, Chiayi County over a 4-year period. A total of 32331 subjects aged ≥40 y were enrolled in this study. The estimated glomerular filtration rate (eGFR) was calculated using the simplified Modification of Diet in Renal Disease (MDRD) equation, and the CKD stage was classified according to the National Kidney Foundation s Kidney Disease Outcomes Quality initiative (NKF-KIDOQI) guidelines. The percentage of participants with late-stage CKD in Chiayi County was 19.5%. Our study clearly demonstrates the regional dependence of the prevalence of late-stage CKD among the surveyed participants after adjustment for age in both male and female populations. The risk of developing late-stage CKD in the middle-aged and elderly population among the 18 townships in Chiayi County was found to exhibit regional and geographical variations, especially in the townships near the mountainside.