We evaluated the chemotactic heterogeneity of eosinophils in Kimura's disease. Patients with Kimura's disease were divided into two groups according to their clinical findings: one group had no other symptoms (KD), and another was accompanied with atopic dermatitis (KD + AD). The chemotactic response of eosinophils from two groups to 5 eosinophil chemotactic factors (ECF) derived from STO-2, an established T cell line. Eosinophils from KD were attracted only by ECF-PI5 and PI6 but not by ECF-PI7, PI8 and PI9. On the other hand, eosinophils from KD + AD responded to all 5 ECF. Eosinophils were further fractionated into normodense and hypodense eosinophils, and assessed for their chemotactic response. We thus found that there was little essential difference in their chemotactic responses to STO-2-derived ECF except ECF-PI9, though random migration of hypodense eosinophils was enhanced. The hypothesis that hypodense eosinophils are in the activated form was not always true, especially in the chemotactic response to ECF.