An exposure method comprises a calculation step of calculating a correction amount of a correction unit which corrects a change in imaging characteristics of a projection optical system based on at least one of parameters including a numerical aperture and effective light source of an illumination optical system, a numerical aperture of the projection optical system, and a size and pitch of a pattern, and an amount of change in environment condition in the projection optical system; and a correction step of making the correction unit operate in accordance with the correction amount calculated in the calculation step.