A circuit board device is provided, including: a first circuit board having a first predetermined connection section; a second circuit board arranged opposite to the first circuit board and having a second predetermined connection section directly facing the first predetermined connection section; and a connector including a first portion and a second portion. The connecter has: a first state where the first portion is arranged at a side of the first circuit board away from the second circuit board, the second portion is arranged at a side of the second circuit board away from the first circuit board, and the first portion and the second portion cooperate with each other to press the first circuit board against the second circuit board; and a second state where the first circuit board is separated from the second circuit board.