Purpose <p>This cross-sectional study explored the association between dietary quality and the risk of depressive symptoms in breast cancer patients.</p> Methods <p>Dietary intake was assessed by 3-day, 24-h dietary recall, followed by dietary quality evaluation by the Chinese Dietary Balance Index-16 (DBI-16). Depressive symptoms were assessed by Center for Epidemiologic Studies Depression Scale (CES-D).</p> Results <p>A total of 160 breast cancer patients with a mean age of 53.07 ± 9.50&#xa0;years were recruited. Fifty of these patients had a CES-D score higher than 16 and were defined as depressed. Compared with non-depressed patients, depressed patients had significantly inadequate fruit intake (<i>P</i> = 0.002). A higher proportion of depressed patients had moderately inadequate dietary intake (lower bound scores, LBS, between 25 ~ 36) compared with non-depressed patients (14.0% <i>vs.</i> 0.9%), and there was a significant difference in the distribution of inadequate intake levels between the two groups (<i>P</i> = 0.003). The depressed patients also had a significantly lower diet variety (<i>P</i> = 0.009). Logistic regression analysis showed that after controlling for age, menopausal status, and employment, LBS was positively associated with depressive symptoms (OR = 1.086; 95% CI 1.005–1.174; <i>P</i> = 0.036), whereas the fruit score (OR = 0.674; 95% CI 0.522–0.871; <i>P</i> = 0.003) and diet variety score (OR = 0.637; 95% CI 0.462–0.878; <i>P</i> = 0.006) were both negatively associated.</p> Conclusion <p>Diet might be one of the determinants of depressive symptoms in breast cancer patients. A balanced diet with more fruits, increased diet variety, and adequate nutrients might be a promising strategy to prevent or treat depressive symptoms in breast cancer patients.</p>