In order to know the initial lens changes that accompany atopic dermatitis (AD), 99 patients diagnosed dermatologically to have AD without any or with slight external ocular inflammations and with no habit of rubbing the eyelid due to severe itching were examined opthalmologically. Clinically, none of them showed any cataractous changes in their eyes. For the sake of comparison with the above population, 4 AD patients with cataractous eyes, 49 renal transplantation patients who were administered steroids over a long period of time but clinically had no cataractous lenses, and 94 healthy individuals with transparent lenses were also selected as subjects. The crystalline lenses of the subjects were examined using an anterior eye segment analysis system and specular microscopy. From Scheimpflug slit images of the lens, light scattering intensity of different lens layers was measured as an indicator of lens transparency changes. The subcapsular basement membrane and changes in the lens epithelial layers were analyzed from specular images of these areas by image processing. Results and considerations from the investigations were: (1) Initial lens changes in cases with AD which may be occult cataractous findings were often detectable. (2) Cataract associated with AD can be accelerated by steroid administration or the habit of strongly rubbing the eyelid, but this may not be the original cause of cataract formation. (3) Two types of cataract are seen in patients with AD: (a) anterior subcapsular plaque formation and (b) anterior and posterior subcapsular opacity formation. The latter type, however, is also accompanied by epithelial damage from the early stage. (4) Significant numbers of patients with AD who have not yet shown manifest lens changes were found among the subjects.