Abstract: Objective To analyze the clinical efficacy and safety of ticagrelor in aged patients with complex coronary disease undergoing primary percutaneous coronary intervention(PCI). Methods Eighty-two elderly patients (> 65 years old) with complex coronary disease undergoing primary PCI in our hospital from Jan. 2013 to Dec. 2014 were included. The patients were randomly divided into clopidogrel group (n=40) and ticagrelor group (n=42). A loading dose of aspirin 300 mg + clopidogrel 600 mg versus aspirin 300 mg + ticagrelor 180 mg were prescribed respectively for the two groups, followed by aspirin 100 mg/d + clopidogre 175 mg/d versus aspirin 100 mg/d + ticagrelor 180 mg/d for maintenance dose from the next day. All the patients were followed up for 12 months. The incidences of cardiovascular ischemic events and major bleeding events were recorded and compared. Results after a 12-month follow-up, incidences of the major adverse cardiovascular events and recurrent angina in ticagrelor group were lower than those of clopidogrel group (0 vs 10%, P< 0.05; 4.8% vs 20.0%. P< 0.05). Dyspnea were more commonly seen in ticagrelor group compared with clopidogrel group (14.3% vs 0, P< 0.05), while no significant difference were shown in severe hemorrhage and stent thrombosis between the two groups. Conclusion In elderly patients with complex coronary disease treated by PCI, ticagrelor can reduce major adverse cardiovascular events compared with clopidogrel. Though a common adverse reaction as dyspnea occurs in ticagrelor group, risk of bleeding doen't increase showing its safety.