Twin pregnancy of a hydatidiform mole with a coexistent live fetus is very rare, and complete molar pregnancy is involved in most cases. A partial molar pregnancy almost always ends in miscarriage due to a triploid fetus. Here, we report a case of a 32-year-old Chinese woman with ultrasound diagnosis of a partial molar pregnancy. Amniocentesis suggested mosaicism, but the fetus was morphologically normal. The woman chose to continue the pregnancy after fully understanding the risk. The infant was delivered prematurely, and the presence of a large single placenta with molar changes. The baby's peripheral blood chromosomes were diploid, and the pregnant woman had no serious complications. The diagnosis, management, and monitoring of this condition will remain challenging because of its rarity. Partial hydatidiform mole combined with pregnancy can result in delivering of a normal fetus and live birth under proper management.