A computer includes an enclosure, a motherboard, at least one expansion card, a supporting bracket, and at least one first baffle plate and at least one second baffle plate. The at least one expansion card is inserted into the corresponding expansion slot. The bracket is located above and spaced from the motherboard by a spacing. The at least one first baffle plate and at least one second baffle plate are arranged along an extension direction of the supporting bracket and extending between the bracket and the motherboard. The at least one first baffle plate covers a part of the spacing between the bracket and the motherboard. The at least one second baffle plate covers another part of the spacing between the bracket and the motherboard. The at least one first baffle plate and the at least one second baffle plate define a plurality of through holes therein.