In this study, we evaluated the protective effect and therapeutic potential of the prostaglandin E₂ (PGE₂) synthetic analog 16,16-dimethyl-PGE₂ (dmPGE₂) in the animal model of pulmonary fibrosis induced by bleomycin. Mice subjected to intratracheal administration of bleomycin (1 mg/kg) received a dmPGE₂ dose of 30 μg/kg/day by continuous subcutaneous infusion. Bronchoalveolar lavage (BAL); immunohistochemical analysis for IL-1, TNF-α, and nitrotyrosine; measurement of fluid content in lung; myeloperoxidase activity assay; and lung histology were performed 1 week later. Lung histology and Sircol assay for collagen deposition were performed 3 weeks after treatments. Changes of body weight and survival rate were also evaluated at 1 and 3 weeks. Compared with bleomycin-treated mice, dmPGE₂ co-treated mice exhibited a reduced degree of body weight loss and mortality rate as well as of lung damage and inflammation, as shown by the significant reduction of: (1) lung infiltration by leukocytes; (2) myeloperoxidase activity; (3) IL-1, TNF-α, and nitrotyrosine immunostaining; (4) lung edema; and (5) histologic evidence of lung injury and collagen deposition. In a separate set of experiments, dmPGE₂ treatment was started 3 days after bleomycin administration, and the evaluation of lung damage and inflammation was assessed 4 days later. Importantly, delayed administration of dmPGE₂ also was able to protect from inflammation and lung injury induced by bleomycin. These results, indicating that dmPGE₂ is able to prevent and to reduce bleomycin-induced lung injury through its regulatory and anti-inflammatory properties, encourage further research to find new options for the treatment of pulmonary fibrosis.