To provide an electronic device, capable of executing upgrade of a program stored in an internal storage medium by the use of an external storage medium, even when a program file of the program is broken down, or the like.

The plotter device 10 includes a storage device 22, a CPU, and a mode-switching circuit. The storage device 22 is arranged within a body. The CPU reads a main program from the storage device 22 and executes it in general start-up. The mode-switching circuit switches, when a switching signal for upgrading the main program by the use of a memory card 30 connected from the outside of the body is input at the start-up, the reading destination of the program from the storage device 22 to the memory card 30 so that the CPU executes an upgrade program stored in the memory card 30.