Background:Hydatidiform mole (HM) is a premalignant disorder characterized by abnormal trophoblastic proliferation. It is predominantly seen in women of reproductive age and often presents with symptoms such as vaginal bleeding. Early diagnosis and management are crucial to prevent complications, including hemorrhage and potential malignancy. The occurrence of massive concealed intrauterine hemorrhage in adolescents with HM is a rare and potentially life-threatening complication. Case: A 19-year-old nulliparous female presented with progressive lower abdominal pain, nausea, and vomiting lasting for one week. The patient's gestational age was determined to be 13 weeks and 5 days based on her last menstrual period. Clinical examination revealed a closed cervical os without uterine bleeding. The imaging studies (ultrasound and MRI) revealed a large intrauterine mass with T2 hyperintensity and multiple cystic spaces, indicative of a hydatidiform mole. Upon performing suction curettage, there was an immediate expulsion of a substantial amount of trophoblastic tissue, accompanied by significant hemorrhage. Histopathological findings, along with positive p57 immunohistochemistry, confirmed the diagnosis of complete hydatidiform mole. The patient experienced a rare complication of massive concealed intrauterine hemorrhage during the course of management. Conclusion: This case highlights the rare yet serious complication of massive concealed intrauterine hemorrhage in adolescents with complete hydatidiform mole. Early diagnosis through imaging, followed by appropriate intervention, is crucial in managing the risks associated with this condition. Timely histopathological evaluation and immunohistochemistry are key in confirming the diagnosis and preventing further complications.