Background: Unilateral twin ectopic pregnancy is extremely rare in natural pregnancy, with an incidence rate of only 1 in 200,000-2,500,000, represents a major health risk for reproductive-aged women, leading to even life-threatening complications. There is a lack of data on the prevalence of this rare disease after in-vitro fertilization-embryo transfer (IVF-ET) cycles. Case Report: We present a case of a 51-year-old woman with rare unilateral twin ectopic pregnancy after frozen embryo transfer treated with bilateral salpingectomy, followed by a review of the literature. Conclusion: Twin ectopic pregnancy is a very rare type of pregnancy that requires a high index of suspicion to diagnose and treat early to prevent complications and maternal death.