To prevent the deterioration of the optical performance of an optical system by efficiently removing scattering particles.

This scattering particle removing device removing scattering particles generated by plasma generation is provided with an electrode plate arranged in an optical path of EUV light radiated from plasma and a voltage applying part which is installed outside the optical path of EUV light and applies a positive voltage or a negative voltage to the electrode plate. The electrode plate is disposed to cross the optical path of EUV light.