Abstract: The invention relates to a housing system for housing electronic components, especially a flat desktop PC or multimedia housing. A fresh-air duct is provided in the interior of said housing and is mounted substantially in parallel to the base plate and spaced apart therefrom at a predetermined height. Said fresh-air duct, apart from lateral air intake openings, is sealed from the housing and at the intake side of the chambers or section that are located in the interior of the housing. At the end of the fresh-air duct facing away from the air intake openings a recess is provided which accommodates the fan. Said fan blows vertically into the chamber below the fresh-air duct, the lower chamber communicating with a lateral exhaust duct. The warmed-up exhaust air is forced through said exhaust duct and is laterally discharged from the housing. In the flow direction below the fan at least one electronic component and one heat source are mounted against which the fan blows.