Background: Previous studies have reported a correlation between some psychiatric disorders and the risk of tinnitus, and there has been much interest in their association. This study employed bidirectional two-sample Mendelian randomization (MR) to investigate the genetic causal relationship between 16 psychiatric disorders and tinnitus. Methods: Independent genetic variants associated with 16 psychiatric disorders and tinnitus were obtained from large genome-wide association studies (GWAS) on European populations. In the MR analysis, inverse-variance weighted (IVW), MR-Egger regression and weighted median estimator (WME) methods were used to estimate the bidirectional causality. In addition, heterogeneity and various sensitivity analyses were performed to verify the validity of the IVs to ensure the robustness. Results: The results of the IVW analysis showed a significant association between depressive disorder and the risk of tinnitus (OR = 1.216, 95% CI = 1.033-1.430, P = 0.019), confirming the possibility of an increased risk of tinnitus due to depressive disorder. Additionally, our study revealed a correlation between insomnia (OR = 2.341, 95% CI = 1.334-4.108, p = 0.003), migraine (OR = 1.095, 95% CI = 1.026-1.168, p = 0.006), neuroticism (OR = 1.457, 95% CI = 1.028-2.067, p = 0.035) and tinnitus based on the IVW approach. In addition, the results of reverse MR analysis showed no significant causal relationships between tinnitus and insomnia, migraine, or neuroticism (P > 0.05), ruling out the possibility of reverse causality. Conclusions: This MR method analysis provides new evidence that psychiatric disorders may be positively associated with tinnitus risk. These results may have important implications for public health policy and clinical practice. Future studies will help to elucidate the biological mechanisms and potential confounders of these associations.