A keyboard device for a keyboard instrument, capable of obtaining excellent touch feeling and stable key stroke without giving sponge feeling or unpleasant vibration during key depression. The keyboard device includes a keyboard chassis, keys pivotally supported on the chassis, hammers swingably supported on the chassis and swinging along with key depression, a hammer upper limit stopper provided on a chassis rear end and contacted by a hammer rear end from below during key depression, and a key lower limit stopper provided on a chassis front end and contacted by front ends of the keys from above during key depression. The hammer upper limit stopper has predetermined flexibility that allows deformation of the hammer upper limit stopper such that after contact of a hammer during key depression, an associated key reaches its lowest position in a state in contact with the key lower limit stopper.