A finger joint rehabilitation exercise aid part includes a rubber part, at least one small bracket, one middle bracket and one large bracket. The small bracket, the middle bracket and the large bracket are fixed on the rubber part and are provided with a fixing hole for fixing a power source. A front end of the rubber part is provided with a finger sheath, and the patient's finger can reach into the finger sheath. As such, according to the finger joint rehabilitation exercise aid part, the rubber part is sheathed on the patient's finger. The rubber part is forced by the power source to bend and straighten and drives the patient's fingers to perform exercise at the same time, thus helping patients perform rehabilitation training.