To provide an auxiliary tool for the exercise of stretching muscles at the back face of a lower limb and those at hips in the state of preventing a knee from bending.

A leg exercise auxiliary tool 1 consists of a means for providing a patch 2 for fixing a thigh F1 and a crus D1 to prevent a knee from bending, a means for providing a curved plate 3 for fixing a sole C1 erected with a little acute angle α1 at the tip 2a of the patch 2 and a means for exercising by raising one's lower-limb tip by his/her own force in both of the fixed states. A lower limb exercise auxiliary tool 11 consists of a means for providing a patch 12 for fixing a thigh F2 and a crus D2 to prevent a knee from bending, a means for providing a curved plate 13 for fixing a sole C2 erected with a little acute angle α2 at the tip 12a of the path 12 and a means for exercising by hanging up one's lower-limb tip passively with the fixed states as menthoned.