An endoscope apparatus comprises a processor comprising hardware. The processor is configured to implement a motion amount calculation process and a focus control process. The processor implements the motion amount calculation process that calculates a plurality of local motion amounts, calculates a correlation between each of the plurality of local motion amounts and a peripheral local motion amount, and calculates the relative motion amount based on a local motion amount among the plurality of local motion amounts that has the correlation higher than a given correlation. And the processor implements the focus control process that calculates a cumulative motion amount by accumulating the relative motion amount over N frames (wherein N is a natural number equal to or larger than 3), and causes the imaging section to perform a focus operation when it has been determined that the cumulative motion amount is larger than the first threshold value.