Objective: To explore the effect of Huangqi-Baoxin decoction combined with conventional western medicine on the cardiac function of the patients with diabetic cardiomyopathy (DCM). Methods: A total of 103 DCM patients who met the inclusion criteria were divided into the control group (51 cases) and the research group (52 cases) by random number table method. The control group was treated with conventional therapy, while the study group was treated with Huangqi-Baoxin decoction on the basis of the control group. Both groups were treated for 3 months. TCM syndromes were scored before and after treatment. The serum GSH-Px, SOD and CRP levels were measured by ELISA. Left ventricular ejection fraction (LVEF) and E/A ratio of early diastolic peak velocity to late diastolic peak velocity (E/A) were measured by echocardiography and then evaluate the clinical efficacy. Results: The total effective rate was 92.3% (48/52) in the study group and 76.5% (39/51) in the control group. There was significant difference between the two groups (χ²=4.922, P=0.027). After treatment, the scores of palpitation, shortness of breath, chest tightness and chest pain, fatigue, hypochondriac mass, spontaneous sweating, edema and total scores in the study group were significantly lower than those in the control group (t values were 10.603, 9.997, 10.546, 10.074, 5.211, 3.981, 6.438, 13.502, P<0.01). After treatment, LVEF (46.03% ± 1.70% vs. 42.33% ± 1.63%, t=11.271) and E/A (1.02 ± 0.17 vs. 0.90 ± 0.16, t=3.796) in the study group were significantly higher than those in the control group (P<0.01). After treatment, the serum GSH-Px and SOD levels in the study group were significantly higher than those in the control group (t values were 7.585, 6.816, P<0.01), and CRP level was significantly lower than the control group (t=10.854, P<0.01). Conclusions The Huangqi-Baoxin decoction combined with routine western medicine therapy can improve the clinical symptoms and cardiac function of DCM patients, reduce oxidative stress injury and inhibit inflammation.