A functional dyed lens for spectacles is obtained by dyeing at least one of the surfaces of an undyed plastic lens, and in the functional dyed lens, a dyeing density defined as a difference in luminous transmittance from the undyed plastic lens is 2% or more but 4% or less, and a difference in average transmittance from the undyed plastic lens in a wavelength region of 530 nm to 570 nm is 3% or more but 5% or less.