A hinge assembly (300) for use in a flat display monitor includes a base seat (10), a fixing seat (20), a pivotal shaft (30), a resilient element (80) and a plurality of washers. The base seat includes a pivot flange (14) having a retaining hole (12) formed therein. The pivot flange defines a protrusion (18) therein, and the protrusion extending into the retaining hole. The fixing seat includes an extending portion (26) defining an engaging hole. The resilient element resists between the base seat and the fixing seat. The pivotal shaft has at least one flat surface, and the pivotal shaft is positioned within the retaining hole of the pivot flange. One of the at least one flat surface pivotably engages with the protrusion. The pivotal shaft extends beyond the retaining hole of the pivot flange, and the plurality of washers is fastened together to the pivotal shaft.