Objective:To explore the differential flora between depression group and control group Based on the GMrepo database of intestinal flora,after excluding the factors such as gender,age,body mass index(BMI),and country,and to further clarify the characteristics of differential intestinal flora in the depression patients with different ages and genders.Methods:The subjects were selected from the GMrepo database with phenotypes of"depression"and"health",and the relevant microbial abundance datasets of the screened research subjects were downloaded based on inclusion and exclusion criteria.Using the case matching function of SPSS 27.0 statistical software,95 control subjects and 95 depression patients were matched into two groups based on gender(1∶1),age(±5 years),BMI(±1.5 kg·mn-2),and country(1∶1);univariate analysis on intestinal flora using non-parametric tests was conducted to screen the differential intestinal flora with a P＜0.05 under hypothesis testing;Wald's forward stepwise selection method was used to construct a binary Logistic regression model,stratified analysis was conducted based on gender(male,female)and age(≤65 years,＞65 years)and the significantly differential flora between the subjects in control group and the patients in depression group were determined based on odds ratio(OR)and P-value within different subpopulatious.Results:Compared with control group,Paraprevotella[OR=0.661,95％confidence interval(CI)=0.489-0.893,P=0.007]and Prevotella(OR=0.946,95％CI=0.903-0.992,P=0.022)showed significantly lower abundance in the patients in depression group,which were the protective factors for the occurrence of depression.Paraprevotella(OR=0.358,95％CI=0.146-0.883,P=0.026)was identified as the differential flora in the male population between depression group and control group,while Faecalibacterium(OR=0.565,95％CI=0.322-0.990,P=0.046)and Alistipes(OR=0.513,95％CI=0.289-0.911,P=0.023)were the differential flora in the female population.Prevotella(OR=0.654,95％CI=0.476-0.899,P=0.009)was the differential flora among the individuals'age≤65 years between depression group and control group.Conclusion:Paraprevotella,Prevotella,Faecalibacterium,and Alistipes are the characteristic intestinal flora associated with depression,and the changes in their abundances may have significant impacts on the occurrence and development of depression.