A portable computer having a decorative cover is disclosed. The portable computer includes a main housing and a display side housing. The display side housing is openably and closably attached to the main housing. Several apertures for forced air cooling are formed in a bottom and a side of the main housing. The decorative cover is configured to cover surfaces of the display side housing and the main housing. A tray having a flat plate member and a spacer are attached to the bottom of the main housing. The spacer is configured to secure a predetermined space between the flat plate member and the bottom of the main housing to form an air flow passage for allowing outside air to pass through the apertures. The spacer is arranged between the decorative cover and the bottom of the main housing.