An endoscope apparatus includes: a region dividing portion that divides an image; a brightness mean calculation portion that has a peripheral brightness mean calculation portion that calculates a peripheral brightness mean value, and a center brightness mean calculation portion that calculates a center brightness mean; a first weighting factor calculation portion that calculates a first weighting factor α; a first photometric value calculation portion that calculates a first photometric value based on a sum total of a value obtained by multiplying a center brightness mean by the first weighting factor α and a value obtained by multiplying the peripheral brightness mean by (1−α); and a brightness adjustment control portion that generates a brightness adjustment control signal for adjusting the brightness of the image based on the first photometric value.