Lupine seed proteins are characterized by a high nutritional value and by functionality, and, owing to these properties they are more and more frequently used in human nutrition. However, its disadvantageous impact on the cells of the man’s immunological system is a factor limiting their use as a food component. For the purpose of investigating this impact, lupine seed proteins (L. angustifolius, Baron variety) were analyzed, and their ability to induce apoptosis in cultured human lymphocytes was examined using a cytometric measurement method of the activity of caspases. Lymphocytes isolated from the blood of an atopic person constituted the investigation material. The cultured lymphocytes were treated with: apoptosis inducer (phytohemagglutinin ‘PHA’) and an extract of the lupine seed protein, respectively. The cytometric analysis of the activity of caspases was performed 48 hours after the cell culture was set up. It was shown that the activity of caspases in lymphocytes was higher compared to a control sample which was treated with an extract of the lupine protein. The results obtained prove that lupine proteins have a potential to induce apoptosis (i.e. an increased activity of caspases) in the cultured human lymphocytes.