Hrastje may refer to:
In Croatia: Hrastje, Croatia, a village in the Municipality of Sveti Ivan Zelina
In Slovenia: Hrastje, Kranj, a settlement in the Municipality of Kranj Hrastje (Ljubljana), a former settlement in the Urban Municipality of Ljubljana Hrastje, Maribor, a settlement in the Municipality of Maribor Hrastje, Šentjernej, a settlement in the Municipality of Šentjernej Hrastje, Šentjur, a settlement in the Municipality of Šentjur Hrastje–Mota, a settlement in the Municipality of Radenci Hrastje ob Bistrici, a former settlement in the Municipality of Bistrica ob Sotli Hrastje pri Cerkljah, a settlement in the Municipality of Brežice Hrastje pri Grosupljem, a settlement in the Municipality of Grosuplje Hrastje pri Mirni Peči, a settlement in the Municipality of Mirna Peč