Continuous exposure to cigarette smoke causes oxidative stress, leading to diseases in the respiratory tract. Secang (Caesalpinia sappan L.) wood is a popular herbal drink in Indonesia due to its antioxidant properties. To date, the protective effects of Secang on the respiratory system have not been widely studied.Ethanolic extract of Secang was prepared by maceration. An in vivo experiment was conducted on 24 male Wistar rats divided into four groups: Control (K), Negative control (KN), low-dose treatment of the extract (P1, 300 mg/kg), and a high-dose one (P2, 600 mg/kg) for 30 days of treatment. After finishing treatments, rats were sacrificed for histological analysis. Rats' average bodyweight showed a consistent increase, indicating tolerable toxicity of the extract, which does not interfere with rats' general health. Serum glutamic pyruvic transaminase (SGPT) and serum glutamic oxaloacetic transaminase (SGOT) depicted consistent results, where P1 and P2 groups significantly decreased (p < 0.001) compared to KN, indicating hepatoprotective activity of Secang.Histologically, tracheal lumen diameter in P2 significantly (p < 0.05) increased compared to KN, suggesting Secang’s potent antioxidant activity. The number of goblet cells increased in KN compared to K, indicating irritation and inflammatory conditions from cigarette smoke. Secang-treated groups exhibited improvement in the lumen diameter, goblet cells, and ciliated epithelium. The findings suggest protective potential of Secang against cigarette smoke-induced tracheal damage.