Abstract: Objective To investigate the effect of Tanreqing injection combined with tiotropium on respiratory function in patients with pneumoconiosis and stable chronic obstructive pulmonary disease (COPD) and its mechanism. Methods A total of 128 pneumoconiosis patients with stable COPD in our hospital from December 2016 to March 2018 were randomized divided into 2 groups, 64 in each group. The control group was received inhalation therapy with Tiotropium bromide aerosol, and the observation group was treated with Tanreqing injection based on control group. The clinical efficacy, clinical symptoms before and after treatment (cough, sputum, arpeggio/wheezing, wheezing/dyspnea, chest tightness/puffiness, poor appetite, abdominal distension, shortness of breath/self-perspiration, flu) scores, lung function (FEV%, FVC, FEV1/FVC), serum IL-1, TNF-α, and TGF-β1 levels of two groups were compared. Results After treatment, the total effective rate of observation group was 90.63%, which was significantly higher than that of control group (73.44%), P<0.05. After treatment, the clinical symptoms scores of two groups were significantly decreased (all P<0.05), and the observation group was significantly lower than the control group (all P<0.05). After treatment, the FEV%, FVC, and FEV1/FVC levels of two groups increased significantly (all P<0.05), and the observation group was significantly higher than the control group (all P<0.05). Serum IL-1, TNF-α and TGF-β1 levels of two groups were significantly lower (all P<0.05), the observation group was significantly lower than control group (all P<0.05). Conclusion Tanreqing injection combined Tiotropium bromide can significantly improve the clinical symptoms and respiratory function of pneumoconiosis patients with stable chronic obstructive pulmonary disease, and its mechanism might be related to the reduce of serum IL-1, TNF-α, TGF-β1 levels and relieve airway inflammation.