An apparatus for opening/closing a cover for an electric curtain, may include a driving device for the electric curtain mounted at a lower part of a withdrawal aperture of a rear package tray, wherein the cover is openably/closably mounted on the withdrawal aperture of the rear package tray; and a cover opening/closing unit disposed between the cover and a drive shaft of the driving device, allowing the cover to be opened or closed simultaneously with a driving of the driving device.