An electronic apparatus, such as a disk apparatus, has a plurality of electronic units such as magnetic head-disk units and at least one power source unit for supplying power to the electronic units. The arrangement of the electronic apparatus is such that, on a frame of the apparatus, the plurality of electronic units are vertically arranged in such a manner as to form a first arrangement system, while the at least one power source unit is arranged in such a manner as to form a second arrangement system above the first arrangement system. The apparatus has an air flow passage for causing cooling air to flow from a lower portion of the electronic apparatus to the inside thereof, pass through the first arrangement system, thereby pass through the second arrangement system, and then be discharged to the outside of the apparatus. This arrangement enables cooling air to flow in a simplified manner, which in turn enhances the cooling efficiency, and also enables electrically connecting cables to be arranged in a simple wiring system.