Disclosed is a cooler of a notebook personal computer allowing more much heat to be rapidly discharged to the outside. The cooler includes: a heat absorbing part fan for absorbing heat generated from a heat generation device of the notebook personal computer; a cooling fan for blowing air in front and side directions; at least two heat pipes of which one ends are in contact with the heat absorbing part and the other ends extend to the front and side of the cooling fan; at least two heat radiation parts provided to be facially in contact with the other ends of the heat pipes; and a lower case having a plurality of grids provided at a corner portion facing the heat radiation parts, from which air heated by the heat generation parts is forcibly discharged.