Introduction: Because of undesirable serum lipoprotein profiles, postmenopausal women are at risk of cardiovascular disease. Soy protein may help protect against these risk factors although its effect on homocysteine and Lp (a) is not clear however, the effects of soy bean in hyperlipidemic postmenopausal women has not been assessed independently yet. The aim of this study was to determine the effects of soy bean on serum concentration of homocysteine, Lp(a) and lipoproteins in hyperlipidemic postmenopausal women. Material and Methods: In a randomised clinical trial with parallel design, 34 hyperlipidemic postmenopausal women were randomly assigned to group 1 and given 130 g soy bean containing 50 g/d soy protein and 159/9mg isoflavones, while group 2 continued their usual diet for 10 weeks (controls). Serum lipoproteins, homocysteine and Lp (a) were measured at baseline and after the 10 th week. Results: There were significant decreases in Lp (a) LDL-c, TC, LDL-c/HDL-c, TG/HDL-c, TC/HDL-c in group 1, as compared to group 2, after ten weeks of study (p<0.05, p<0.001, p<0.01, p<0.01, p<0.05 and p<0.05 respectively) at the end of the study. Similarly, Lp(a), homocysteine, LDL-c, TC, LDL-c/HDL-c, TG/HDL-c, TC/HDL were significantly decreased ( p<0.01, p<0.05 p<0.01, p<0.01, p<0.01, p<0.05, p<0.01) at the end of the study, compared with initial values of the soy group. Conclusion: We can conclude that Soy protein reduces CVD risk in postmenopausal women because of both modest reductions in serum lipoproteins and Lp(a) in hyperlipidemic postmenopausal women.