Provided are a lens device, an imaging apparatus, and a filter unit capable of suppressing occurrence of ghosts and flares. The lens device includes a first optical filter and a second optical filter in order from an object side in an optical path. The first optical filter is composed of an optical filter (for example, a band-pass filter) that has a light transmission band in a specific wavelength region. The second optical filter is composed of an optical filter (band-stop filter) that has a light absorption band in a wavelength region which is different from the light transmission band of the first optical filter.