The fire fighting system at the highrise building doing according to a preferred embodiment of the present invention comprises the fire sensing part which is configured to output the fire sensing signal in case of being equipped inside the highrise building and sensing fire acceptance and rejection at the highrise building; the fire fighting control computing device which draws the firing location of the highrise building in which fire occurs according to the fire sensing signal and it transmits the control signal for the fire fighting drone in case the firing location deviates from the ladder coverage of the fire truck and is configured to transmit the window control signal which is to open the window of the firing location adjacent to the outside of the highrise building; the window *** which is connected to the window frame and is configured to open the window of the firing location according to the window control signal; and the fire fighting drone which is connected to the fire hydrant of the highrise building rooftop to the equipped fire hose and it takes off in the rooftop of the highrise building and is configured to spray the digestive fluid according to the control signal for the fire fighting drone in the outside of the highrise building through the above-mentioned opened window towards the firing location.