The purpose of this study was to verify the effects of a repeated hemodialysis diet education program on dietary knowledge, dietary self-care compliance, and physiological indices in older adults on hemodialysis. Methods: This study employed a non-equivalent control group pre-post repeated measures design. Based on Ebbinghaus' forgetting curve, the experimental group received diet education four times. Data were analyzed by the x 2-test, t-test, and Fisher's exact test. A repeated measures ANOVA was used for hypothesis testing. Results: There were statistically significant between-groups differences in dietary knowledge by time of assessment, within group differences by time of assessment, and interactions between group and time. Regarding dietary self-care compliance, there were significant within-group differences by time of assessment and interactions between group and time. There were significant within-group changes in inter-dialytic weight gain by time of assessment. For the physiological indices, blood sodium and albumin showed significant within-group changes by time of assessment. Phosphorus and blood urea nitrogen scores showed significant within-group changes. For blood potassium concentration, there was a significant difference in interactions between group and time. Conclusion: Owing to the resulting improvements in dietary knowledge and self-care compliance, the repeated education program applied in this study can be used as a preventive measure for complications in older adults on hemodialysis.