A patient with hairy cell leukemia who developed mediastinal mass and fever is described. A CT-guided aspiration of the mass yielded Salmonella tiphymurium. Granulocyte response to infection was intact and could explain the favorable course of this unusual Salmonella infection. Although several reports deal with salmonellosis as a complication of immunodeficiency states, this type of infection is of rare occurrence in hairy cell leukemia.