Background: Choriocarcinoma is an aggressive trophoblastic malignancy characterized by rapid progression and a strong tendency for early hematogenous metastasis. It may occur in gestational or nongestational forms. Nongestational choriocarcinoma is extremely rare and is most commonly reported in young women. The tumor frequently metastasizes early to organs such as the lungs, liver, and brain. Case presentation: We report the case of a 21-year-old woman who presented with dyspnea and hemoptysis and was initially treated for pneumonia. Further evaluation revealed nongestational choriocarcinoma with pulmonary and hepatic metastases. Diagnosis: Contrast-enhanced computed tomography of the chest initially suggested pulmonary artery thromboembolism; however, the diagnosis was ultimately confirmed by histopathological examination. Conclusion The distinctive feature of this case is that the disease presented with clinical and radiological findings mimicking pulmonary artery thromboembolism. This case highlights the importance of considering metastatic choriocarcinoma in young women presenting with unexplained respiratory symptoms, hemoptysis, and atypical pulmonary vascular findings.