A portable electronic device includes a main body and a power converter. The main body includes a first housing and a main circuit disposed within the first housing. The main circuit includes a power input end located on a side surface of the first housing. The power converter includes a second housing and a power modulating circuit. A side surface of the second housing is detachably assembled to the side surface of the first housing. The modulating circuit is disposed in the second housing, and includes a power output end and a utility power input end. The power output end is located on the side surface of the second housing, and the utility power input end is located on another side surface of the second housing. The power modulating circuit is capable of modulating utility power from the utility power input end to modulated power suitable for the main circuit, and the modulated power s outputted from the power output end. When the side surface of the second housing is assembled to the side surface of the first housing, the power output end on the second housing is electrically connected to the power input end on the first housing thereby transmitting the modulated power to the main circuit.