A composite panel assembly includes: a first composite panel having first and second contact surfaces, and including upper and lower protective layers, and a first core; and a second composite panel having third and fourth contact surfaces, and including upper and lower protective layers, and a second core. The first contact surface of the first composite panel is disposed above and abuts against the third contact surface of the second composite panel, and the second contact surface of the first composite panel is disposed below and abuts against the fourth contact surface of the second composite panel.