A keyboard apparatus of this electronic musical instrument is provided with touch curves TW1 through TWp, TB1 through TBq each defining a velocity value Vc varying with a key-depression velocity Kv (TD). Each of keys K1 through Kn of a keyboard 14k is associated with one of the touch curves TW1 through Twp, TB1 through TBq by touch selecting tables SW, SB in accordance with an equalization rule and a weighting rule. Upon a key-depression, in accordance with the velocity curve TWr, TBs selected on the basis of an actual depressed key position Ki (M2), an actual key-depression velocity Kva is converted into a velocity Vca for controlling emission of a tone (M3).