Purpose <p>This study examined the association between weekly walking amount and self-rated health among adults and tested whether depression mediates this relationship.</p> Subject and methods <p>Data were drawn from the 2023 Korea Health Panel Survey. The final sample included 8982 adults aged 20&#xa0;years or older with no missing values on the main study variables and covariates. Self-rated health was the dependent variable, weekly walking amount was the independent variable, and depression was the mediator. The weekly walking amount was calculated by combining the number of walking days and walking duration per day during the previous week and was then log-transformed. Depression was measured using the EQ-5D anxiety/depression item. Data were analyzed using SPSS and PROCESS macro model 4, with 5000 bootstrap resamples used to test the indirect effect.</p> Results <p>Weekly walking amount was negatively correlated with depression and positively correlated with self-rated health, whereas depression was negatively correlated with self-rated health. In the mediation analysis, weekly walking amount had a significant negative effect on depression and a significant positive effect on self-rated health. Depression also had a significant negative effect on self-rated health. The direct effect of weekly walking amount on self-rated health remained significant after depression was entered into the model. The bootstrap confidence interval for the indirect effect did not include zero, indicating a significant partial mediating effect of depression.</p> Conclusion <p>Greater weekly walking amount was associated with better self-rated health in adults, and this relationship was partially mediated by depression. These findings suggest that walking may contribute not only to physical health perception but also to mental well-being, highlighting the value of integrating walking promotion and emotional support in adult health promotion strategies.</p>