A total of 25 buffaloes aged between 4-10 years, from in different villages surrounding Mansoura city to follow fetal membrane drop after normal parturition. Sixteen of them with normal dropped fetal membrane (control) and nine with retained fetal membrane were used in this study. For the first 8 weeks after parturition each buffaloe was subjected to clinical examination, bacteriological examination and haematological and biochemical studies. Bacteriological examination of 256 uterine swabs of control buffaloes showed that 65 (24.4%) swabs were bacteriologically positive. Yielded 74 isolates mainly E. coli (33.8%). Meanwhile for retained fetal membrane buffaloes 144 uterine swabs, 108 (75.0%) were bacteriologically positive with 1.9% pure single aerobic and faculitative anaerobic cultures; 14.8% pure single anaerobic and 83.3% mixed cultures. They yielded 362 isolates comprising 176 (48.6%) aerobic and faculitative anaerobic bacteria with the most predominant ones were A. pyogenes (17.4%) and E. coli (9.9%) and obligate anaerobic bacteria 186 (51.4%) mainly Bacteroides Spp. (24.9%) and Fusobacterium necrophorum (14.9%). Sensitivity test for those isolated bacteria revealed that the most of isolates were highly sensitive to clindamycin, enrofloxacin, ceftioufur, neomycin, tetracycline and penicillin. The changes in blood and serum of retained fetal membrane buffaloes when compared with control group, revealed that: Presence of significant decrease in the level of glucose & total cholesterol & calcium & phosphorus & selenium and high significant decrease in the total count of erthrocytes, leucocytes and vitamin C level. On the other side significant increase was observed in the level of S. AST, S.ALT and triglyceride. High significant increase were noticed in S.LDH, YGT, blood urea, Creatinine, cortisol and progesterone levels