The electronic musical instrument, which is suitable for generating sustaining tone of a rubbed string instrument, has a manipulator for achieving performance manipulation in a linear manipulation region or in a plane manipulation region to simulate the motion of a bow of the rubbed string instrument, and a processing circuit for applying smoothing treatment to signals given by the manipulator. The musical tone generated by the electronic musical instrument can be prevented from being contaminated with discordant sound caused by noise produced in performance manipulation.