To improve the erectility of penis and to make easily wearable the same with comfortability with respect to male sexual function disorders such as impotence by mounting a projection on the outer peripheral surface of an annular body made of an elastic body to exclude the mental pressure of an user.

The supporter body 1 is integrally molded from an elastic body such as rubber, and this elastic body is optionally made of a pure transparent material or a material including a luminous pigment. A projection 4 is erected as one rod slightly curved from an annular body 2 of the supporter body 1, and a side part of its point 9 is projected from a point surface 6 of an opening 3 of the supporter body 1. The inner surface 7 of the opening 3 has a taper shape widened from the basic end surface 5 toward the point end surface 6, and a protrusion part 8 is formed on the basic end surface 5 side. To use the supporter, the penis is inserted into the expanded opening 3 to wear the same. On this occasion, a basic part of the penis is fastened by the protrusion part 8 to increase the erectility by inhibiting the backflow of the blood and to keep the erection.