An magnetic tape cassette of the type in which the tape is wound on flangeless hubs and the tape is pulled out through an opening in the cassette for recording and reproducing having improved tape winding characteristics. An annular projection is formed around each of the flangeless hubs, and a rib having about the same height as the annular projection extends radially outwardly from the radial projection in an area corresponding to the first-wound portion of the tape. The rib keeps the tape from deviating sideways as it is initially wound onto the hub.
