Allergic and immunopathological diseases of the ocular surface are inflammations that can occur with mild to severe symptoms that cause visual impairment. Allergic inflammations mainly affect the conjunctiva, causing acute and/or chronic conjunctivitis. Several forms are distinguished: seasonal allergic conjunctivitis, vernal conjunctivitis, atopic keratoconjunctivitis, contact allergy, giant papillary conjunctivitis. The most common is the seasonal form, which is linked to seasons. Allergic ocular surface processes require local treatment with artificial tears, anti-allergic eye drops. If complications occur, topical corticosteroid and cyclosporin treatment may be used. Immunopathological inflammations of the ocular surface are associated with systemic diseases. Keratoconjunctivitis sicca, although occurring in the absence of systemic disease, is a common companion of Sjögren’s syndrome and collagen diseases. Ocular pemphigoid belongs to the group of mucous membrane pemphigoids. After the initial conjunctivitis symptoms, subconjunctival fibrosis begins, leading to the development of sym- and ankyloblepharon. In the final stage, the ocular surface is covered by scar tissue (ocular cicatricial pemphigoid) which practically results in loss of vision. Peripheral ulcerative keratitis is usually associated with collagen vascular disease, rheumatoid arthritis. A 3-4 mm long, curved infiltration starting near the limbus becomes ulcerated and then perforates, on which the iris may prolapse. First, systemic treatment is required, which is an interdisciplinary task. Topical corticosteroid and cyclosporine eye drops may be administered. In the case of corneal perforation, amniotic membrane transplantation and/or keratoplasty may be performed. Orv Hetil. 2023; 164(43): 1686-1692.