Abstract: A fastening device for different components is proposed. The device may include a first member having a through passage formed at a connecting end, and a second member including an insertion groove, into which a connecting end of a first member is introduced, and an inlet hole and an outlet hole, which are formed on the opposite side of the insertion groove to communicate with each other through the through passage. The device may also include a connector for fastening or releasing according to a rotational operation position while being inserted to reach the inlet hole, the through passage, and the outlet hole; and a damper positioned on one side of the connector and configured as a single elastic pressing body that prevents rotation of the connector and maintains a fixed state of the connector by contracting or restoring its original shape according to a rotational operation of the connector.