The invention provides a large-thickness boron carbide and aluminum alloy composite board. The composite board comprises a boron carbide ceramic board body and an aluminum alloy wrapping layer, the aluminum alloy wrapping layer wraps the outer surface of the boron carbide ceramic board body, and the ceramic board body is provided with a through hole; the through hole axially penetrates through thealuminum alloy wrapping layer and the boron carbide ceramic board body. Anti-cracking holes are uniformly formed in the ceramic board body, so that flowing and penetrating of liquid aluminum in the pouring process are facilitated, and binding of aluminum alloy and boron carbide ceramic is firmer.