The present disclosure provides a gamma tuning method and a gamma tuning device. The gamma tuning method includes steps of: comparing grayscale binding points of a to-be-debugged module with a standard gamma curve; determining a to-be-tuned grayscale binding point from the grayscale binding points of the to-be-debugged module in accordance with a comparison result between the grayscale binding points of the to-be-debugged module and the standard gamma curve; and tuning a grayscale brightness value of the to-be-tuned grayscale binding point in accordance with a target brightness value of the grayscale binding point on the standard gamma curve.