SUMMARY A case of acretism placentae is described in a 24 years-old patient, 3 gravida, 2 cesarean, who consulted for abundant red brilliant hemorrhage. After physical examination a diagnosis of partial occlusive placenta previa was done. During cesarean section invasion of peritoneum by placenta and strong fixation of it to bladder was observed. Sub-total hysterectomy and uterocistectomy was performed.