An electronic device with infrared touch input function is provided. The electronic device includes a display unit defining an information display area; an infrared input device including a circuit board having two pairs of oppositely disposed sides defining an open area corresponding in size and shape to the information display area, at least one light emitting device; a linear array of light detecting devices faced to light emitting devices, connected together via first resistances respectively to form a node; an analog/digital (A/D) converter configured to convert a voltage across the node into digital values; a micro-processing unit for determining an infrared light path being obstructed; and the CPU configured for controlling the display unit displaying a plurality of menu options, determining the menu option being touched; and performing functions corresponding to the menu option.