Abstract： Objective To explore the differentially expressed microRNA(miRNA)in pleural effusion of patients with tuberculous pleurisy(TP)and its relationship with autophagy.Methods A total of 10 patients with TP(case group)and 10 other patients with pleural effusion(control group)attending the authors'hospital were selected for total RNA extraction from pleural fluid and miRNA sequencing analysis in order to detect the differential expression of miR-NAs expression profiles;pleural effusion from 20 patients with TP and 20 non-TP patients attending the same period of time were further selected for verification of miRNAs expression profiles.Subsequently,the diagnostic significance of 6 of the differently expressed miRNAs was confirmed by reverse transcription polymerase chain reaction(RT-PCR),receiver operating characteristic(ROC)curves and authenticity assessment of another portion of the population sample.Finally,the study selected miR-21-5p to predict its autophagy-related genes and autophagy proteins interactions.Results A total of 73 differentially expressed miRNAs were screened by chip system analysis.RT-PCR results showed that compared with control group,miR-3148,miR-4701-3p in case group up-regulated;miR-223-3p,miR-23a-3p,miR-7a-5p and miR-21-5p were down-regulated in the case group.The ROC curve results showed that the area under the curve of the diagnos-tic performance of miR-7a-5p,miR-23a-3p,miR-21-5p,miR-223-3p,miR-3148,miR-4701-3p for TP were 0.787,0.944,0.832,0.878,0.919,0.732 respectively.The top 5 genes with the highest correlation with miR-21-5p as predic-ted by bioinformatics analysis in conjunction with Human Autophagy Moderator Database(HAMdb)were BECN1,MAPK1,FOXO3,HSPA8 and RAB11 A.Conclusion The miRNAs in tuberculous pleural effusion(TPE)have diagnos-tic value for TP,6 miRNAs in the study,provides new markers and potential therapeutic targets for the diagnosis and treatment of TP,and it is hypothesized that miR-21-5p may regulate autophagy through autophagy-related genes affecting the pathogenesis and outcome of TP,which de-serves further study.