Abstract: The present invention provides a placental preparation, its preparation method and medical uses in cancer treatments. Said placental preparation is a fraction having molecular weight less than 3 kDa obtained from a postpartum placenta of a mammal including human. The placental preparation according to the present invention has an excellent selective cytotoxicity toward tumor cells and in turn an excellent antitumor activity without any undesired side effect, and is thus very useful in cancer treatment.