A portable toolbox is disclosed. The portable toolbox includes a frame and a holder. The holder can hold a plurality of bits. The holder is put in the frame so that the holder can be pivoted between a retreated position and an extended position relative to the frame. In the retreated position, the bits are kept in the holder in cooperation with the frame. In the extended position, the bits can be put onto and taken from the holder from two opposite sides of the frame.