The present invention is an electric slit width adjusting system of a slit-lamp microscope consisting of a light slit width adjusting mechanism of the slit lamp, an adjustment motor and a teletype operating mechanism. The light slit width adjusting mechanism of the slit lamp includes a mechanical drive controlling the slit width. The adjustment motor is arranged on the light slit width adjusting mechanism and controlled by the teletype operating mechanism through electrical signals. The teletype operating mechanism with a function of precisely controlling the rotation angle of the adjustment motor is arranged above the operating handle of slit lamp mobile platform (or the base of slit lamp mobile platform).