Abstract: An electronic musical instrument having a single-tone priority function includes touch detection value storage means for storing a touch detection value that pertains to an ON key, priority key selection means for selecting the first priority key out of ON keys when detecting a key OFF event, tone generation means for generating a tone corresponding to the first priority key selected by the priority key selection means, tone volume computation means for computing a tone volume of the tone generated by the tone generation means on the basis of a touch detection value that pertains to the priority key stored in the touch detection value storage means, and a touch detection value that pertains to the latest key event, and tone generation control means for controlling to generate the tone in the tone volume computed by the tone volume computation means, thereby allowing a legato play with a natural tone volume with respect to a play made so far.