Pregnancies resulting in viable fetuses are extremely rare in accompanying a hydatiform mole, often due to the development of maternal complications, including preeclampsia and vaginal bleeding. The risk for gestational trophoblastic neoplasm is another concern because of the delayed evacuation of the molar tissue. In this paper, the authors present a case of complete mole hydatifonn with a live co-twin fetus (CHMLF) resulting in the delivery of a healthy male infant with the partial regression of the molar tissue and the decline of serum beta human chorionic gonadotropin (beta-hCG) during the pregnancy. In the management of CHMLF, each patient must be considered individually and eligible patients can be followed in the absence of serious maternal complications. Serial ultrasound examinations and close clinical and laboratory surveillance of the mother are certainly indicated.