Objectives: . This study investigated the 8-year incidence and progression of hearing loss (HL) and its types and examined the risk factors for changes in HL. Methods: . This longitudinal cohort study analyzed data from the Korean Genome and Epidemiology Study (KoGES), an ongoing, prospective, community-based cohort study that has been conducted since 2001. Altogether, 1,890 residents of urban areas in Korea aged 45–75 years at time 1 (baseline) were included in the study. Pure-tone audiometry (PTA) testing was performed twice, at time 1 (2008–2009) and time 2 (2015–2018, follow-up), 8 years apart. HL grades were defined as seven mutually exclusive categories following the revised World Health Organization classification. Incidence was defined as PTA >20 dB HL in the better ear at time 2 among those without HL at time 1. Progression was defined as the progressive deterioration of HL among those with HL at time 1. The three types of HL constituted sensorineural (SNHL), conductive, and mixed HL. Results: . At time 1, 36.40% of patients were diagnosed with HL, which increased to 51.64% at time 2. The 8-year incidence of HL was 27.20%, and progressive deterioration of HL occurred in 23.11% of those with HL. SNHL was the most common type of HL, and its prevalence markedly increased at time 2. Multivariate analysis demonstrated that the incidence of HL was significantly associated with increasing age, male sex (odds ratio [OR], 1.73; 95% confidence interval [CI], 1.07–2.81), and diabetes mellitus (OR, 1.43; 95% CI, 1.04–1.96). Alcohol consumption was a risk factor for HL deterioration among those with HL at time 1. Conclusion . The prevalence and deterioration of HL were extremely high among older adults, and age was the strongest risk factor for these changes. Therefore, timely screening and intervention are necessary to prevent HL and delay its deterioration among older adults.