Idiopathic pulmonary fibrosis (IPF) is a dreadful, chronic, and irreversibly progressive disease leading to death with few effective treatments. Our previous study suggested that repetitive hyperbaric oxygen (HBO) treatment alleviates bleomycin-induced pulmonary fibrosis in mice, but the underlying mechanism is not clear. In this study, we compared the RNA-seq data from bleomycin challenged mouse lung tissues with or without repetitive HBO treatment, to figure out the affected biological processes and pathways. Combined with integrative analysis of public data from GEO, our study support HBO treatment as a viable strategy against pulmonary fibrosis. Overall design: Six to eight weeks old male C57BL/6 mice (20-25 g) after bleomycin instillation were randomly divided into bleomycin (BLM) group and BLM+HBO group in day 7 post bleomycin instillation. Then mice in BLM+HBO group were exposed to repetitive HBO treatment (2.5 ATA, 90 min/time/day) for 14 consecutive days, while the mice in the BLM group were placed in the chamber for the same duration without pure oxygen pressurization. The lung tissues were collected at day 21. RNA-seq based on next generation sequencing was applied with 4 samples in bleomycin group and 3 samples in bleomycin + HBO group.