Abstract: An integral composite fiber is formed by integrally joining a stretchable fiber and unstretchable fibers. The stretchable fiber has longitudinally extending first exposed surfaces that are circumferentially spaced from each other. The unstretchable fibers has longitudinally extending second exposed surfaces each disposed between a circumferentially adjacent pair of the first exposed surfaces. One of the first exposed surfaces has a larger surface area than the other or others of the first exposed surfaces. Said other or each of the others of the first exposed surfaces has a surface area ratio of less than 0.8 with respect to the surface area of said one of the first exposed surfaces.