Background <p>With the aging population increasing, it is important to identify effective psychological and spiritual support factors to help individuals experience the aging process in a healthier and more meaningful way. This study aims to examine the effect of spiritual transcendence and kinesiophobia on successful aging.</p> Methods <p>A quantitative cross-sectional descriptive survey method was used in this research. The study was conducted between February and July 2025 with 871 elderly individuals. Hierarchical regression analysis was performed using SPSS 25.0. Machine learning analysis and estimation were performed using the R programming language version 4.1.3.</p> Results <p>The mean age of the participants was 70.75 ± 5.40. According to regression analysis, the level of spiritual transcendence explains 51.9% of the level of successful aging (R²=0.519), and this relationship was found to be statistically significant (t = 30.619, p&lt;0.001). When spiritual transcendence and kinesiophobia levels were evaluated together, the explained variance ratio reached 67.5% (R²=0.675). An increase in spiritual transcendence (t = 14.122, p&lt;0.001) and a decrease in kinesiophobia (t=–20.418, p&lt;0.001) show a statistically significant relationship with the level of successful aging. SHAP values show the extent to which each variable influences the model’s predictions and the magnitude of this influence. According to these values, kinesiophobia is identified as the most important variable in predicting the successful aging variable.</p> Conclusions <p>The findings from our study indicate that supporting the psychological and spiritual resources of older adults plays an important role in strengthening the successful aging process. Longitudinal studies on successful aging are recommended.</p>