Background: Gut microbial dysbiosis has been implicated in the pathogenesis of depression. Dietary interventions offer promising microbial-targeted therapeutics for depression. However, limited evidence exists regarding the associations between dietary live microbe intake and the prevalence of depression, as well as its impact on mortality risks. Methods: This study included 28,133 participants from the U.S. National Health and Nutrition Examination Survey (2005-2018), and ascertained their underlying causes of death. Weighted logistic regression was utilized to assess the relationships between live microbe intake and risks of depression and suicidal ideation. Independent and joint associations between live microbe and mortality outcomes were evaluated using multivariable Cox regression and Kaplan-Meier survival curves to calculate relative risks. Results: In the fully adjusted model, participants with high dietary live microbe intake had a significantly lower prevalence of depression (OR = 0.727, 95%CI: 0.627,0.844) and suicidal ideation (OR = 0.778, 95%CI: 0.648,0.935) than those with low intake. The multivariable-adjusted HRs for individuals in the G1 were 1.217 (95%CI, 1.081, 1.370) for all-cause mortality and 1.307 (95%CI, 1.029,1.661) for cardiovascular disease mortality, compared to participants in the G3. Kaplan-Meier survival analysis revealed that cumulative hazard of cardiovascular mortality was progressively lower among participants with depression in the G3 than those without depression. Conclusions: Higher live microbe intake was associated with a lower prevalence of depression and suicidal ideation, and was linked to significantly decreased risks of all-cause and cardiovascular mortality. Further larger prospective studies are essential to verify the health effects of live microbes, and personalized dietary recommendations are necessary.