A modular floor tile has a first side and a second side opposite to the first side. The first side has a first male locking structure with a male locking end. The second side has a female locking structure with a locking receptacle, which has a receiving groove, a locking notch vertically adjacent the receiving groove, and a female locking end adjacent the locking notch, such that the male locking end of a first one of the floor tile is insertable into the receiving groove of a second one of the floor tile, and vertically movable from the receiving groove into the locking notch to engage with the female locking end of the second one of the floor tile, thereby engaging the first male locking structure of the first one of the floor tile with the female locking structure of the second one of the floor tile.