The mixed tumors are common benign tumor of salivary gland, but are rarely found in maxillary (or paranasal) sinus. Pleomorphic salivary adenoma of nasal cavity and maxillary sinus has been reported by Harrison in 1956, and thereafter reported by many authors. The autor had experienced a case of mixed tumor of maxillary sinus which occurred in a 12 year old female. The tumor mass was removed through Denker's modification approach and postoperative course was uneventful for 2 1/2 years of follow-up.