This study investigated the clinical value of coronary arteriography (CAG) combined with fractional flow reserve (FFR) in the treatment of coronary heart disease (CHD) with coronary artery stenosis exceeding 70%. A retrospective analysis was conducted on 344 patients with CHD treated at the Gansu Institute of Cardiovascular Science from January 2020 to May 2022. The patients were divided into the CAG group (n = 138) and the CAG + FFR group (n = 206). Among these patients, those with coronary artery stenosis exceeding 70% underwent an FFR functional examination to accurately determine indicators for coronary intervention. The data collected included demographic information, number of stents, number of vascular lesions, treatment methods, and the occurrence of major adverse cardiovascular events (MACE) at the 6-month follow-up. No significant differences were found between the 2 groups in terms of age, gender, underlying diseases, body mass index (BMI), smoking history, and blood lipid profile. The rate of surgical treatment in the CAG group and the CAG + FFR group was 88.41% and 43.69%, respectively. The CAG + FFR group showed a 44.72% reduction in the need for surgical treatment and a reduced number of stents placed, which helped prevent overtreatment. Additionally, there was no statistical difference between the 2 groups in MACE such as angina pectoris, myocardial infarction, and sudden cardiac death at the 6-month follow-up. After combined CAG examination with FFR measurement, the number of CHD patients with coronary artery stenosis exceeding 70% requiring surgical intervention decreased by 44.72%. FFR could significantly prevent overtreatment and provide more precise guidance for CHD treatments.