A circuit board assembly is provided and includes a first circuit board, a second circuit board and a first connecting module. The first connecting module includes a first connecting wire, a first connector and a second connector. The first circuit board includes a first processor, and the second circuit board includes a second processor. One end of the first connector is connected to one end of the first connecting wire, and the other end of the first connector is connected to the first circuit board. One end of the second connector is connected to the other end of the first connecting wire, and the other end of the second connector is connected to the second circuit board. The first connector is adjacent to the first processor, and the second connector is adjacent to the second processor.