A propeller shaft (1) includes a first shaft (10) having a yoke at one end, a second shaft (20) slidably connected to the other end of the first shaft, and a surface treated member (30) which is arranged at a connecting portion, at which the first shaft and the second shaft are connected to each other, and to which surface treatment (32) for improving slidability of the second shaft with respect to the first shaft is applied. The surface treated member is formed by a substrate which is separate from the first shaft and the second shaft and to which the surface treatment has been applied. The surface treated member (30) is arranged at the connecting portion, at which the first shaft and the second shaft are connected to each other, after the surface treatment is applied.