In the paper, an in silico analysis was performed for the purpose of assessing the cross-reactivity of peanut (Arachis hypogea L.) proteins, and special attention was paid to the Ara h 9 protein, a marker for cross-reactivity concerning fruit proteins. There were determined possible cross-reactions, which might occur among various proteins of peanut as well as among peanut proteins and other food allergen proteins including the commonly known proteins of soybean, lentil, tomato, hazelnut, common apple, and peach, and, also, some other proteins such as, inter alia, Chinese lychee and date palm fruit. Using UniProtKB and BIOPEP databases as well as the EVALLER software database, the matching degree of peanut protein epitope sequences (> 80 %) was determined mainly against soybean, tomato, hazelnut, apple and peach epitopes.