A heat sink device for a display card includes a heat sink, the heat sink having a base and a plurality of heat-dissipating fins on the base, the base having two hooks respectively beside two lateral sides of the groove; a heat-dissipating fan, having a blade wheel and a power wire for the blade wheel, the blade wheel being on the base and the power wire being inside the groove of the base; and a fastener, having two engagement parts respectively corresponding to the hooks, wherein the fastener covers the groove so as to position the power wire by means of engagement of the hooks with the engagement parts. Therefore, the power wire of the heat-dissipating fan can be properly arranged on the heat sink.