Background <p>Depression and anxiety are the emotional problems most frequently experienced by older adults. We aimed to investigate the associations between successful aging (SA) and depression and anxiety in older adults from Ningbo, China.</p> Methods <p>A cross-sectional study of 6,672 community-dwelling adults aged 65 years or older was performed. SA, depression, and anxiety symptoms were self-reported and measured using the Successful Aging Inventory (SAI), Patient Health Questionnaire-9 item (PHQ-9), and the 7-item Generalized Anxiety Disorder scale (GAD-7), respectively. Linear and logistic regression analyses were used to estimate the associations of SA with depression and anxiety.</p> Results <p>After multivariate adjustment, we found that the SAI score was independently associated with the PHQ-9 and GAD-7 scores (β = −0.069 and − 0.048, respectively). Multivariate-adjusted spline regression models showed negative, nonlinear dose–response associations between the SAI score and both depression and anxiety symptoms (<i>P</i>_{for nonlinearity} = 0.001 for both). With the highest quartile set as the reference, we determined that the lowest SAI score quartile was independently associated with both depression symptoms (OR = 16.131, 95% CI: 8.423, 30.892) and anxiety symptoms (odds ratio [OR] = 10.926, 95% confidence interval [CI]: 5.268, 22.664). In subgroup analyses, the association between the SAI score and depression symptoms was significantly higher in rural than in urban areas (<i>P</i>_{for interaction} = 0.024).</p> Conclusion <p>Among older adults in Ningbo, China, SA was found to play an important role in depression and anxiety symptoms, suggesting the need for effective and feasible interventions to promote SA in Chinese older adults.</p>