Abstract: Objective To investigate the clinical therapeutic effective of low-molecular weight heparin (LMWH) in patients with unstable angina(UA). Methods One hundred and sixty-two UA patients were randomly divided into control and treatment group. Patients in treatment group had a therapy of LMWH (0.1 ml/10 kg,twice a day). Results The total effective rate in treatment group was 93.8% and 74.0% in control group (P<0.05).Meanwhile the LMWH decreased the frequency and duration of angina pectoris, nitroglycerin consumption, and improved hameorheology(P<0.05). Conclusion LMWH is a valuable therapy for UAP patients.