A turbine engine fan rotor having a disk carrying blades, a substantially frustoconical cover mounted on the disk, and axial retention device for retaining the blades and including a ring mounted in an annular groove in the disk and forming a bearing surface for roots of the blades. The ring is festooned or crenellated and co-operates with a festooned radial annular lip of the disk. The rotor also has at least one axial tooth inserted in hollow portions of the ring and of the lip of the disk. Two coaxial parts arranged radially inside the disk have respective first and second fastener flanges for fastening to the disk, said flanges being axially interposed between the cover and the disk, being circumferentially offset relative to one another, and being fastened independently of one another to the disk.