Recently we experienced two cases of reticulum cell sarcoma histopathologically verified which is supposed to be rare. One was a 63-year-old male who had the tumor of the left tonsillar area; the other was a 12-year-old girl with the mass on the nasopharynx. It must be emphasized that early biopsy should be done for pathological diagnosis in case of unilateral enlargement of one tonsil as sociated with mild hyperemia and discomfort and also in case of nasopharyngeal tumor producing bleeding and nasal obstruction.