In a variable resistor of the type wherein there is formed on an insulating substrate a resistive member having wide portions and narrow portions in the sliding direction of a slide member and ends thereof wired respectively to a ground terminal and an input terminal. A plurality of contact elements formed on said slide member are brought into sliding contact with said resistive member and a high resistance film allowing the passage of electrostatic charges therethrough is formed at portions of said insulating substrate lying within the sliding passage of said contact elements so that a part of said contact elements comes into contact therewith when it comes off from said resistive member.