Objective To investigate the effect of ramipril on progression of nonculprit lesions in patients with ST-elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (PPCI). Methods A total of 200 patients (60.1 ± 11.3 years) with STEMI who underwent successful PPCI from January 2010 to December 2013 were enrolled in this study. All patients underwent PPCI as treatment for culprit lesions. Patients were divided into two groups according to the dosage of ramipril used at hospital discharge as follows: high dosage group (2.5–10 mg, q.d.) and low dosage group (1.25–2.5 mg, q.d.). Clinical and angiographic follow-up was performed for 12 months. The primary endpoint was clinically-driven percutaneous coronary intervention (PCI) for nonculprit lesions. The clinical and angiographic features were analyzed. Results Clinical and angiographic follow-up was performed with 87 patients in the high dosage group and 113 patients in the low dosage group. The numbers of patients who underwent additional PCI were six and 20 in the high and low dosage groups, respectively. The rate of having additional PCI performed was lower in the high dosage group than in the low dosage group (6.90% vs. 17.70%, P = 0.03). Conclusions A high dosage of ramipril may prevent progression of nonculprit lesions, which could be the major cause of recurrent PCI in patients with STEMI after PPCI.