Objective To investigate the G protein-coupled receptor kinase 2 (GRK 2) level in peripheral blood lymphocytes with cardiac func-tion in elderly patients with acute myocardial infarction. Methods This study enrolled 40 patients with acute ST-segment elevation myo-cardial infarction (STEMI) and 40 patients with unstable angina. All patients were 65 years or older. Cardiac function was evaluated by echocardiography, and the GRK 2 level in peripheral blood lymphocytes was measured. Patients with STEMI were followed up for 2 years. Results The GRK 2 level in peripheral blood lymphocytes was significantly higher in patients with STEMI than in patients with unstable angina, and was negatively correlated with left ventricular ejection fraction, cardiac output, stroke volume, and left ventricular fractional shortening. The GRK 2 level was significantly elevated in some patients with acute STEMI and poor cardiac function. Conclusions In-creased GRK 2 level in patients with acute STEMI may contribute to poor myocardial systolic function and myocardial remodeling. Meas-urement of the GRK 2 level in peripheral blood lymphocytes may assist in the evaluation of cardiac function and myocardial remodeling in elderly patients with acute STEMI.