A dissipating device configured to dissipate the heat energy generated by the heat sources in the electronic devices. When the dissipating device contacts the heat sources, the heat energy can be absorbed by the dissipating device. The working fluid is stored within the dissipating device such that the working fluid can undergo a phase transition after the dissipating device absorbs heat energy. Then the working fluid can circulate inside the dissipating device. Accordingly, the heat-dissipation mechanism, which is applied to the dissipating device contacting the electronic devices, can be effectively sped up. The dissipating device is formed into a thin structure to achieve an excellent heat-dissipation effect with a limited heat-dissipation area.