Abstract: An automatic foldable emergency ladder system for use in a building having a smoke detecting device includes an inverted L-shaped housing having a horizontal portion and a vertical portion and being securely mounted to a perimeter wall of a roof of the building; a control unit mounted in the horizontal portion of the housing and having at least one input port for receiving a signal from the smoke detecting device; an electrically powered driving device mounted in the horizontal portion of the housing and electrically connected to the control unit for receiving a signal therefrom and being activated/deactivated therefor; a spool unit rotatably mounted in the housing and driven by the driving device; a foldable ladder securely coupled to the vertical portion of the housing at one end thereof and having at least one wire which is secured to the spool means at one end thereof and an opposite end thereof is coupled to a free end of the foldable ladder such that the ladder can be folded/extended by the spool unit;