Cross-reactivity has important consequences in some immune disorders, including allergic and autoimmune diseases, which can affect both diagnostic and therapeutic approaches. One of the most common cross-reactivity syndromes is pollen-food syndrome (PFS). The patient is sensitized with pollen by the airways and exhibits an allergic reaction to food antigen with a structural similarity to the pollen. PFS usually presents with pruritus and swelling of the mouth and throat during or just after ingestion of fresh, uncooked fruits and vegetables. Latex fruit syndrome is another cross- reactivity syndrome. It is the association of latex allergy and allergy to plant foods, which affects up to 50% of latex-allergic patients. Here, we present two cases with cross-reactivity syndrome.