Woman meets various kinds of symptoms during menopause, it may include physical and psychological changes,whrle osteoporosis is the major health problem in this phase in addition to cardiovascular disease. This research aimed to study the effect of soy flour on some biological parameters in ovariectomized rats. including blood lipid, blood pictures and differential count of lymphocytes. The study was performed on female Albino rats that divided into six groups, one group was sham operated and fed standard diet, the other five groups were  the ovarictomized, one group was fed on the standard diet, while the remaining four groups  were  fed with soy flour in percents of (25,50,75,100 %) of meal protein.After eight weeks the  body weight of food intake , Food Efficiency Ratio (FER), Protein Efficiency Ratio(PER), internal body organs were also measured  and blood lipid and, CBC, and differential count of lymphocyte ware determined . The results showed that soya flour consumption improved the nutritional status, FER,PER, blood lipids, and increased hemoglobin levels. Therefore, the researcger recommends postmenopausal women to eat soy flour ,soybeans and soy products which is rich in isoflavons that improve estrogen hormone level, hence reduces osteoporosis, heart  and cardiovascular diseases risks