Abstract：Objective：To observe the clinical efficacy of Sanzi Xiapo Decoction combined with western medicine in treating patients with overlap syndrome（OS）of chronic obstructive pulmonary disease（COPD）and obstructive sleep apnea hypopnea syndrome（OSAHS）. Methods：A total of 61 inpatients with OS of phlegm-blood stasis obstructing lung type，treated in the Pulmonary and Critical Care Medicine（PCCM）Ward of the Ninth Department at Dongguan Hospital，Guangzhou University of Chinese Medicine between November 2021 and May 2024，were enrolled. They were divided into two groups using a random number table method：30 cases in the treatment group and 31 cases in the control group. The control group was treated with western medicine，and the treatment group was treated with Sanzi Xiapo Decoction combined with conventional western medicine. The course of treatment in both groups was 14 days. The traditional Chinese medicine syndrome score， scores of Epworth Sleepiness Scale（ESS）， apnea hypopnea index （AHI）， lowest peripheral oxygen saturation（LSpO 2 ）at night， pH value of arterial blood gas， partial pressure of carbon dioxide（PCO 2 ）in arterial blood，partial pressure of oxygen（PO 2 ）in arterial blood，and levels of serum white blood cell count（WBC），C-reactive protein（CRP），procalcitonin（PCT），malondialdehyde（MDA），superoxide dismutase（SOD）and nuclear factor κB p65（NF-κB p65），as well as the clinical effects were observed and compared between the two groups before and after treatment. Results：After treatment，the total effective rate of the treatment group was higher than that of the control group（P＜0.05）. Traditional Chinese medicine syndrome scores and ESS scores significantly decreased in both groups compared to baseline（P＜0.05），and these scores in the treatment group were significantly lower than those in the control group（P＜0.05）. LSpO₂ significantly increased（P＜0.05）and AHI significantly decreased（P＜0.05）in both groups compared to baseline. The LSpO₂ in the treatment group was significantly higher than that in the control group（P＜0.05）；however，there was no significant difference in AHI between the two groups （ P＞0.05）. The pH of arterial blood gas and PO 2 in the two groups were increased，and PCO 2 was decreased compared with those before treatment，the differences being statistically significant（P＜0.05）. The treatment group exhibited significantly higher pH of arterial blood gas and PaO₂，and significantly lower PaCO₂ compared to the control group（P＜0.05）. Serum levels of WBC，PCT，CRP，MDA，and NF-κB p65 significantly decreased（P＜0.05）， while SOD levels significantly increased（P＜0.05）in both groups compared to baseline. These improvements were significantly more pronounced in the treatment group：serum WBC，PCT，CRP，MDA，and NF-κB p65 levels were significantly lower，and SOD levels were significantly higher than in the control group（P＜0.05）.Conclusion：Sanzi Xiapo Decoction combined with western medicine can effectively alleviate the core clinical symptoms of OS patients of phlegm-blood stasis obstructing lung type， reduce hypoxia， inflammatory response and oxidative stress， and the mechanism of action may be related to the regulation of NF-κB signaling pathway.