The present invention relates to a heat-dissipating device and a method for manufacturing the same. The heat-dissipating device includes a base and a first heat-dissipating fin. The outer periphery of the base has a trough. The first heat-dissipating fin has a first heat-dissipating portion, a first end and a second end. The first end and the second end are disposed in the trough. By a machining process, both ends of the first heat-dissipating fin are pressed into the trough of the base at a high speed, so that the base can be combined with the first heat-dissipating fin rapidly. In this way, the manufacture cost is reduced and the heat-dissipating efficiency is increased.