A keyboard apparatus includes a frame including a first contacting portion, a second contacting portion, and a first rib, a first member having a first side and a second side opposite to the first side and being attached to the frame, and a plurality of keys being attached to the frame, the first contacting portion being in contact with the first member from the first side, the second contacting portion being in contact with the first member from the second side, the first rib having longitudinal shape in a first direction, and the first contacting portion in the first direction with respect to the first rib.