Abstract: OBJECTIVE To explore the potential molecular mechanism of human umbilical cord mesenchymal stem cell exosomes(hUCMSC-Exo) in alleviating pulmonary hypertension(PH). METHODS The hUCMSC-Exo were high-throughput sequenced after extracted and identified. PH target was searched in GeneCards. PH-related chip GSE53408 and GSE113439 were downloaded from GEO databases and screened for the differential genes after batch correction. The target genes in GeneCards and GEO databases and the target regulated genes predicted by miRNAs contained in hUCMSC-Exo were used for intersection. The protein-protein interaction network was constructed to screen out the key targets of hUCMSC-Exo acting on PH, then went for GO and KEGG analysis. RESULTS Forty-three high expression miRNAs were collected after hUCMSC-Exo sequenced. A total of 17 miRNAs might affect PH through prostate cancer, HIF-1 signaling pathway, PI3K-Akt signaling pathway, proteoglycans in cancer and pathways in cancer. CONCLUSION This study provides a new idea for exploring the role of hUCMSC-Exo in alleviating PH.