Aim To observe the effect of warfarin to angina pectoris and asymptomatic myocardical ischemia (AsMI) after percutaneous coronary intervention (PCI). Methods 86 cases with angina pectoris or AsMI after PCI were divided into 2 groups. The control group was normative treatment. The therapy group was add Warfarin except normative treatment. It is compared in relieve or disappear time of angina pectoris and the times of AsMI stroke and total ischemia burden and side effects of warfarin in the two groups. Results The relieve time of angina pectoris in therapy and control groups are 3.28 ± 1.67 d and 4.98± 1.69 d (p<0.01), respectively. The disappear time of angina in the two groups are 8.87 ± 0.60 d and 11.04 ± 3.68 d ( P< 0.01), respectively. The effective rate to treatment of angina pectoris are 90.0% and 73.9% ( P< 0.05), respectively . The AsMI stroke difference of total ischemia burden in the two groups are 659.1 ± 257.6 mm· s and 369.7 ± 297.2 mm· s (P< 0.01), respectively. It is explanation that the therapy group have significant clinical effects in angina pectoris and AsMI after PCI compare with control group. Side effects of warfarin have bleeding but no so serious. Conclusion The studydemostrated that warfarin had effect of important assist therapy to angina pectoris and AsMI after PCI. It is safety as careful use.