ABSTRACT Aim To sensitize clinicians regarding possibility of heterotopic pregnancy even in spontaneous conceptions. Background Though heterotopic pregnancy is a rare condition, its incidence is rising, which varies from one in 8,000 to 30,000, more in assisted reproductive technique conceptions. It is being commonly misdiagnosed. Here, we present a case of heterotopic pregnancy after spontaneous conception, diagnosis of which was confused with ovarian torsion. Case Report A 31-year-old second gravid para one with one living issue at 12 week 6 day period of gestation presented to emergency with acute-onset pain in right lower abdomen for 3 days. On examination, an ovarian tumor with ascitis with probable torsion was suspected along with intrauterine pregnancy. These findings were further supported by similar ultrasound picture. Patient was taken up for laparotomy. Intraoperative finding was suggestive of heterotopic pregnancy with ruptured left tubal ectopic pregnancy. Left salpingectomy was done with minimal uterine manipulation. Histopathology showed blood clots, hyalinized villi, and acute inflammatory cell infiltrate suggestive of ectopic pregnancy. Ultrasonography (USG) done in the postoperative period showed viable intrauterine pregnancy. The patient is currently following with us and is in her second trimester of pregnancy. Conclusion Heterotopic pregnancy is a diagnostic and therapeutic challenge; a high index of suspicion is required. It is important for clinicians to see adnexal in detail even if intrauterine pregnancy has been seen clearly during USG, especially in high-risk cases. Clinical significance Heterotopic pregnancies can occur even in the absence of high-risk factors. In patients with intrauterine pregnancy, who present with adnexal mass with free fluid in abdomen, clinicians should keep their mind open for possible diagnosis of heterotopic pregnancy. Early diagnosis and surgical management will decrease maternal morbidity and increase chances of survival of intrauterine pregnancy. How to cite this article Vatsa R, Meena J, Kumar S, Zangmo R, Bharti J, Roy KK. Successful Outcome of Spontaneously Conceived Heterotopic Pregnancy masquerading Ovarian Torsion. J South Asian Feder Obst Gynae 2017;9(1):60-62.