A lower limb function training device which the patient themselves can use safely with no sense of fear, which is used to prevent or improve a drop foot contracture or to expand the excursion of a joint while preventing the patient from using it over an appropriate amount of exercise to the utmost, which allows the patient to select the type of exercise, and which enables measurement of state of the body. The device is provided with a foot rest support structure, a foot rest drive mechanism and a round-trip movement sensing device, and a brake device for braking the round-trip movement of the foot rest when the count reaches a preset value. The device is provided with a foot rest support structure, a foot rest drive mechanism and at least one contact sensor on a surface of the foot rest, and a brake device for braking the back-and-forth movement of the foot rest when the at least one contact sensor detects the soles of the feet contacting.