Electronic apparatus and data recording method in electronic apparatus

In a vehicle-installed AV device (100), the power is supplied to various sections of the vehicle-installed AV device (100) via a key switch (2) from a battery (1) of a vehicle. The vehicle-installed AV device (100) is provided with: a predicting/detecting section (101) for detecting a running state of the vehicle to predict an engine stop; a flash memory (102) and a main memory (103) for storing operation data of the vehicle-installed AV device (100); and a CPU (104) for controlling the flash memory (102) and the main memory (103). When the predicting/detecting section (101) predicts the engine stop, the operation data stored in the main memory (103) is written into the flash memory (102).