An electronic device and housing thereof are provided. The electronic device includes housing, a partition, multiple electronic elements, and a fan. The housing has a side edge, where the side edge is provided with a slit. The partition is disposed in the case, is separated by a distance with the slit, and divides the interior of the case into a first and a second space. The partition has a through hole, the second space is in communication with the first space through the through hole, and the first space is in communication with the outside of the case through the slit. The electronic elements and the fan are disposed in the second space, and an air outlet of the fan is adjacent to the through hole, so that air in the second space can be driven to flow from the first space to the outside through the slit.