A method and an apparatus for opening continuous filaments provide stable quality of fibrous layer after opening crimped TOW. The TOW is transported by means of a plurality of rolls. While transported, the TOW is applied a resistance on one side of the TOW by slidingly contacting a sliding body onto the TOW at between rolls. As a result, continuous filaments stacked in a thickness direction of the TOW are caused to sift in a transporting direction of the TOW. Thus, the TOW is opened and the continuous filaments are spread in a width direction of the TOW.