A keyboard apparatus has a plurality of white keys and black keys each of which pivot. The keyboard apparatus also has a plurality of reaction force generation members 21w and 21b provided for the white keys and the black keys, respectively. The reaction force generation members 21w and 21b have dome portions 21w1 and 21b1, respectively, which are thin and shaped like a dome so as to be elastically deformed by depression, and base portions 21w3 and 21b3, respectively, which are thick and are formed integrally with the dome portions 21w1 and 21b1 to support the dome portions 21w1 and 21b1, the base portions 21w3 and 21b3 jutting outward from respective lower end surfaces of the dome portions 21w1 and 21b1. The vertical position of the lower end of the dome portion 21w1 is displaced from the vertical position of the lower end of the dome portion 21b1.