A storage node, a phase change memory device, and methods of operating and fabricating the same are provided. The storage node may include a lower electrode, a phase change layer on the lower electrode and an upper electrode on the phase change layer, and the lower electrode and the upper electrode may be composed of thermoelectric materials having a melting point higher than that of the phase change layer, and having different conductivity types. An upper surface of the lower electrode may have a recessed shape, and a lower electrode contact layer may be provided between the lower electrode and the phase change layer. A thickness of the phase change layer may be about 100 nm or less, and the lower electrode may be composed of an n-type thermoelectric material, and the upper electrode may be composed of a p-type thermoelectric material, or they may be composed on the contrary to the above. Seeback coefficients of the lower electrode, the phase change layer, and the upper electrode may be different from each other.