Molar pregnancy presents a pathologic condition requiring surgery of the uterus promptly as possible although hydatidiform mole itself is a benign disease. In order to remove the mole as quickely as possible, early diagnosis is desirable. In actual practice however, definite preoperative diagnosis by clinical manifestation is impossible since which is vague or altogether absent symptoms especially in first trimester. Hysterography by transabdominal injection is very valuable and easy procedure for accurate diagnosis of hydatidiform mole which shows typical homey combed, moth eaten or sponge pattern on roentgenography. We have experienced 68 cases of hydatiform mole during last five and half years. Among them hysterography by transabdominal route was done on 26 cases and shows 96% diagnostic accuracy. One missed case was turned out to be missed abortion. The absence of accidents indicates the harmlessness of this method. We feel the best approach in making diagnosis of hyatidiform mole among clinically borderline and in conclusive for mole pregnancy and its differential diagnosis is by use of transabdominal hysterography.