To estimate prevalence of severe-profound hearing loss (HL) in South Korea, and analyse a 10-year trend of HL according to age, sex, and region by using a nationwide population-based database. Retrospective review from Korean National Health Insurance Service from 2006 to 2015. The degree of severe-profound HL was classified into six grades, based mostly on HL worse than 60 dB HL for both ears. Absolute number of HL was the highest in 2011 (0.25 million; males, 0.14 million; females, 0.11 million); it decreased gradually until 2015. Total HL prevalence was the highest in 2010 (0.5%; 251,954), and decreased annually to 2015 (0.46%; 237,272). The trend of HL prevalence showed a gradual decrease from 2010 to 2015. Prevalence of severe-profound HL was always higher in the male population (1.19 times higher than female in 2015). Prevalence of HL was higher in rural areas than in urban areas (1.4 times higher in 2015). Number of severe-profound HL in South Korea decreased gradually in all age groups annually, even though some older age groups had the highest peak in 2010-2011. Prevalence of severe-profound HL decreases gradually in all age groups annually in South Korea, although the absolute number of HL cases increases rapidly among those aged over 80 years.