Objective To observe the clinical efficacy of modified Sanzi Yangqin Decoction for the treatment of obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods Totally 80 cases of OSAHS patients were randomly divided into treatment group and control group, with 40 cases in each group. Both groups received intervention of diet and life. The control group was given vitamin C, 100 mg each time, 3 times a day orally. Treatment group was given modified Sanzi Yangqin Decoction, 1 dosage per day, twice a day, orally, for 14 d. The scores of TCM symptoms, sleep apnea (AHI), lowest oxygen saturation (LSaO2) and longest apnea were observed before and after treatment. Results The overall effective rate of TCM syndrome was 90% (36/40) in the treatment group and 65% (26/40) in the control group, with statistical significance (P<0.05). Compared with before treatment, there was statistical significance in the scores of TCM symptoms, AHI, LSaO2, and longest apnea (P<0.05,P<0.01). After the treatment, compared with the control group, there was statistical significance in the scores of TCM symptoms, AHI, and LSaO2 in the treatment group (P<0.05,P<0.01). Conclusion Modified Sanzi Yangqin Decoction can effectively treat OSAHS and improve the life quality of patients.