An electronic apparatus includes a rear casing, a front cover, and an electronic assembly that includes a display module, a host module, a battery module, and an expansion module. The rear casing has a front opening. The front cover is located on the front opening; the front cover and the rear casing together constitute an accommodation space. The display module is installed inside the accommodation space and stacked over the front cover. The host module is installed inside the accommodation space and stacked over the display module. The battery module is installed inside the accommodation space, stacked over the display module, and arranged side by side with the host module. The expansion module is installed inside the accommodation space and stacked over the battery module. The expansion module includes an expansion circuit board stacked over the battery module and a plurality of card connectors mounted on the expansion circuit board.