To compare the sonographic findings of a partial mole with a complete mole, we prospectively investigated ultrasonographic findings of early intrauterine pregnancies with vaginal bleeding in the aspect of the presence of the gestational sac, fetal pole, subchorionic hemorrhage, and molar vesicular pattern. Among 16 cases of complete mole, the characteristic snowstorm appearance of a vesicular pattern was found 10 cases(62.5%), while inhomogenous echoes, which suggested bleeding and/or necrosis, were noted in 6 cases(37.5%). In the cases of 14 partial moles, findings were as follows: gestational sac(12 cases, 85.7%), fetal pole(6 cases, 42.8%), vesicular pattern(7 cases, 50%), and hemorrhage(3 cases, 21.4%). Two cases of hydatidiform mole with midtrimester normal fetus were found, one with the complete mole and the other with partial mole. Sonographically, we can easily differentiate the partial mole from the complete mole when the gestational gas is present. However, difficulty in distinguishing the 2 types of mole still exists when the sonographic findings show only a vesicular pattern and hemorrhage.