Peroxynitrite is involved in the pathogenesis of pulmonary diseases such as asthma, occupational pulmonary diseases and acute respiratory distress syndrome (ARDS) due to excessive production of nitric oxide or superoxide or both. Lornoxicam, a new oxicam derivative, is a potent anti-inflammatory agent. In this study, we evaluated the role of lornoxicam in a peroxynitrite-induced pulmonary and tracheal injury model by measuring myeloperoxidase (MPO) activity, malondialdehyde (MDA) and 3-nitrotyrosine (3-NT) levels in lung tissue and bronco-alveolar lavage fluid. The study protocol was based on three experimental groups as treatment (T), control (C) and peroxynitrite (P). Each group was subdivided into three subgroups as 2nd, 24th and 48th hour groups. P and T groups were injected intratracheal peroxynitrite. The T group received intraperitoneal lornoxicam before and 24h after peroxynitrite installation. Tissue and serum MDA, MPO values and tissue 3-NT value of the treatment and control groups were found significantly lower than the peroxynitrite group at the 2nd, 24th and 48th hours (p<0.05). Similarly, values obtained from bronco-alveolar lavage fluid examination in the control and treatment groups were significantly less than those in the peroxynitrite group (p<0.01). Therefore, Lornoxicam has been found to be effective in attenuating peroxynitrite induced pulmonary and tracheal injury in rats.