Abstract：Objective： To observe the effect of Zhengan Xifeng Decoction combined with Wendan Decoction on behavioral and psychological symptoms （BPSD） and serum thyroid hormones in the treatment of Alzheimer's disease （AD）. Methods： A total of 60 AD patients treated at the Third Hospital of Quzhou from January 2022 to January 2023 were divided into the control group and the trial group according to the random number table method，with 30 cases in each group. The control group was treated with routine anti-dementia medicines， and the trial group was additionally treated with Zhengan Xifeng Decoction combined with Wendan Decoction in addition to routine antidementia medicines. The two groups were compared in terms of BPSD indicators [Behavioral Pathology in Alzheimer's Disease Rating Scale （BEHAVE-AD）， Neuropsychiatric Inventory （NPI）， Scale for the Assessment of Positive Symptoms （SAPS）]， serum thyroid hormones [triiodothyronine （T3）， thyroxine （T4）]， adverse reactions， and clinical effects. Results：The total effective rate in the trial group was 93.33%（ 28/30），compared to 60.00%（ 18/30） in the control group， with a significant difference between the two groups （P＜0.05）. After treatment， the scores of BEHAVE-AD， NPI， and SAPS in the two groups were decreased when compared with those before treatment （P＜ 0.05）， and the scores in the trial group were lower than those in the control group （P＜0.05）. After treatment， the levels of T3 and T4 in the two groups were increased when compared with those before treatment （P＜0.05），with the trial group showing higher levels than the control group （P＜0.05）. During the treatment period， the incidence of adverse reactions was 16.67% （5/30） in the trial group and 26.67% （8/30） in the control group， with no significant difference between the two groups （P＞0.05）. Conclusion： Zhengan Xifeng Decoction combined with Wendan Decoction can effectively reduce behavioral and psychological symptoms in AD patients， improve serum thyroid hormone levels and enhance clinical efficacy.