An electronic device housing includes a housing body, a movable foot pad mechanism disposed in housing body, a ventilation grille, a fan, and a fan switch connected electrically to the fan. The movable foot pad mechanism includes a foot pad pivoted to a bottom wall of the housing body. The foot pad is turnable pivotally to prop up the housing body so as to increase a space below a bottom of housing body. When the foot pad is being turned pivotally to prop up the housing body, the ventilation grille is moved simultaneously so as to make the space inside the housing body open to the ambient environment, and the fan is activated for heat dissipation, thereby increasing the heat dissipation efficiency of the electronic device housing.