A one-piece car charger includes an enclosure and a circuit board. The circuit board is received in the enclosure and is electrically connected to a power output port. The enclosure is integrally formed as a one-piece configuration. The one-piece enclosure helps reducing manufacturing time (and is applicable to automatized manufacturing process). There is no need for operators to manually assemble the enclosures one by one so that the assembling time is shortened and mistakenly assembling incorrect parts is eliminated.