Abstract: A touching rib of an input unit is provided. The input unit comprises the touching rib and a pressing portion including a top face and a bottom face. The present touching rib comprises a main body and at least one auxiliary structure. The main body is disposed on the bottom face for touching an electronic switch in a predetermined distance. The main body has a first predetermined height. The auxiliary structure is formed integrally with the main body and disposed on the bottom face and side by side with the main body. The auxiliary structure has a second predetermined height shorter than the first predetermined height. The auxiliary structure is needed for maintaining the main body having an accurate height, which is corresponding to the first predetermined height, and a smooth surface for touching the electronic surface.