An electronic device capable of being configured flexibly with modules of different specifications includes: a main body having a slot opening formed at the front of the main body and communicated with a slot space in the main body, slot rails disposed on at least one sidewall of the slot space of the main body and module slots communicated with the slot rails respectively; and a modular device, including electronic modules, each having at least one module rail slidably coupled to the slot rail. The module slots in the slot space are configured to be corresponsive to the module spaces respectively, and the module spaces serve as plug-in spaces for installing the electronic module and the module spaces are communicated with one another. The electronic device provides module application spaces for multifunctional applications and installing and applying modules of different specifications flexibly.