An endoscope system includes: an endoscope having an image sensor configured to image an inside of a subject; a processor configured to perform predetermined image processing on a video signal that is imaged by the image sensor; a storage that is provided in the endoscope, the storage being configured to store compressed data obtained by compressing data volume of first non-compressed data that is used for correction of an image imaged by the image sensor; a restoring circuit configured to read the compressed data from the storage to restore the compressed data to the first non-compressed data when data is transferred from the endoscope to the processor; and an image correcting circuit that is provided in the endoscope, the image correcting circuit being configured to correct the image imaged by the image sensor by using the first non-compressed data restored by the restoring circuit.