Background and AimsEosinophilic esophagitis (EoE) has been increasingly diagnosed globally. However, there have been few general population-based studies in Asia. The aim of this study was to investigate EoE epidemiology in the Japanese general population. MethodsWe analyzed an employer-based health insurance claim database from January 2005 to September 2022. EoE cases were identified based on the International Classification of Diseases-tenth Revision code, K20.0. We calculated the incidence and prevalence of EoE using Poisson regression and binomial distribution, respectively. Using 10 matched controls for each EoE case, a nested case-control study was performed to identify potential risk factors for EoE. ResultsOf 15,200,895 individuals, 1,010 EoE cases were identified. The incidence and prevalence of EoE were 2.82 (95% CI 2.44–3.26) per 100,000 person-years and 10.68 (95% CI 10.01–11.37) per 100,000 people in 2022, nearly three and eight times as high as those in 2017, respectively. Smoking was associated with decreased risk of EoE (OR 0.45 (0.36 to 0.56), p<0.001) whereas alcohol consumption (OR 1.51 (1.21 to 1.88), p<0.001) were associated with increased risk of EoE along with several allergic conditions and psychiatric disorders. EoE was not related to either body mass index or lifestyle-related diseases such as hypertension, diabetes mellitus, hyperuricemia, and dyslipidemia. ConclusionThe incidence and prevalence of EoE in Japan have steadily increased over the past two decades. Nevertheless, EoE remains less common in Japan compared to the United States and Western Europe. Factors contributing to the epidemiology of EoE on a global basis may improve our understanding of the contribution of genetic and environmental risk factors.