Pregnancy at the site of cesarean section is an uncommon form of ectopic pregnancy which is associated with delayed diagnosis and late treatment may cause maternal mortality. This paper reports an ectopic pregnancy on the site of an earlier cesarean section. The patient is a 33-year-old woman with history of a normal delivery and a cesarean section and a uterine curettage in the past year who complained of unintentional uterine bleeding despite consistent use of combined contraceptive pills. Last menstrual period was 12 Sep 2017 and the patient reported abnormal uterine bleeding. In pregnancy tests, and after ultrasound for pregnancy, a uterine cavity without a pregnancy sack was observed. To make the final diagnosis, transvaginal ultrasonography was applied which proved ectopic pregnancy with fetal heartbeat at six weeks and two days. The patient was then referred to a clinic and pregnancy termination was started by injection of potassium chloride into the embryo and the mother received Methotrexate. The history of cesarean section and curettage can cause ectopic pregnancy. So, in the case of abnormal uterine bleeding, despite the use of contraceptive pills, pregnancy examinations should be done to avoid further complications. According to this study, administration of potassium chloride into the embryo and Methotrexate to the mother is an appropriate method in terminating ectopic pregnancy at the site of a previous cesarean section.