A laser system according to one aspect of the present disclosure includes a wavelength-variable first solid-state laser device configured to output a first pulse laser beam; a wavelength conversion system including a first nonlinear crystal configured to wavelength-convert the first pulse laser beam and a first rotation stage configured to change a first incident angle of the first pulse laser beam on the first nonlinear crystal; an excimer amplifier configured to amplify a pulse laser beam wavelength-converted by the wavelength conversion system; and a control unit configured to receive, from an external device, data of a target center wavelength of an excimer laser beam output from the excimer amplifier, control a wavelength of the first pulse laser beam in accordance with the instructed target center wavelength, and control the first incident angle on the first nonlinear crystal in accordance with an average value of the target center wavelength.