Objective: To observe the efficacy and safety of TCM syndrome differentiation-guided herbal intervention for patients with five constitutions during the high-risk window period of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) based on TCM constitution theory. Methods: A total of 300 AECOPD patients in the high-risk window period (54–66 cases for each constitution) were randomly divided into two groups (150 cases each). The control group received fluticasone furoate/umeclidinium/vilanterol inhalation therapy, while the experimental group was additionally given constitution-specific TCM decoctions (e.g., Erchen Decoction combined with Sanzi Yangqin Decoction for Phlegm-Dampness constitution). The treatment course was 8 weeks with a 6-month follow-up. CAT score, TCM syndrome score, pulmonary function, 6-minute walking distance (6MWD), and levels of CRP and IL-6 were observed. Recurrence and safety indicators were recorded. Results: After treatment, all indicators improved significantly in both groups (p < 0.05), with the experimental group showing superior improvements in CAT score, TCM syndrome score, FEV1, 6MWD, and inflammatory indicators (p < 0.01). The recurrence rate was lower in the experimental group during follow-up (p < 0.05). No severe adverse reactions or abnormalities in liver/kidney function were observed in either group. Conclusion: TCM syndrome differentiation treatment guided by constitution theory can improve symptoms, quality of life, and pulmonary function, reduce inflammatory levels and recurrence rate in AECOPD patients during the high-risk window period, with good safety.