Objective To investigate the correlation between serum levels of microRNA-25 (miR-25) and microRNA-873 (miR-873) with cardiac function and degree of coronary artery stenosis in patients with coronary heart disease (CHD). Methods One-hundred CHD patients diagnosed by coronary angiography admitted to our hospital from August 2019 to October 2020 were collected as the study subjects (CHD group), 100 healthy individuals who were examined in our hospital during the same period were collected as the control group, and the serum levels of miR-25 and miR-873 were compared between the two groups. According to the NYHA cardiac function grading, there were 38 CHD patients of NYHA grade Ⅰ-Ⅱ, 35 of NYHA grade Ⅲ, and 27 of NYHA grade Ⅳ. The serum levels of miR-25 and miR-873 were compared among each group. According to the Gensini score, all CHD patients were grouped into mild group (35 cases), moderate group (41 cases), and severe group (24 cases), and the serum levels of miR-25 and miR-873 were compared in each group. Pearson method was applied to analyze the relationship between serum miR-25 and miR-873 levels, cardiac function indicators, and the degree of coronary artery stenosis in CHD patients. Results The serum levels of miR-25 and miR-873 in the CHD group were lower than those in the control group (P＜0.05). The serum levels of miR-25 and miR-873 in NYHA Ⅲ and NYHA Ⅳ patients were lower than those in NYHA Ⅰ-Ⅱ patients (P＜0.05); the serum levels of miR-25 and miR-873 in NYHA grade Ⅳ patients were lower than those in NYHA grade Ⅲ patients (P＜0.05). As the severity of mild, moderate, and severe illness increased, serum levels of miR-25, miR-873, and LVEF decreased sequentially, while LVEDD LVESD levels and Gensini score increased sequentially (P＜0.05). Correlation analysis showed that Gensini score, LVEDD, and LVESD were negatively correlated with serum levels of miR-25 and miR-873 (P＜0.05); LVEF was positively correlated with serum levels of miR-25 and miR-873 (P＜0.05). Conclusion The serum levels of miR-25 and miR-873 in CHD patients decrease, and they are obviously correlated with cardiac function and the degree of coronary artery stenosis