Basaloid squamous cell carcinoma (BSCC) is a rare and aggressive version of squamous cell carcinoma (SCC) that preferentially occurs in the upper aerodigestive tract. Since the first description by Wain SL et al., in 1986, only 21 cases with BSCC in the nasal cavity or in the paranasal cavity have been reported in the English literature. We present a case of BSCC arising in a paranasal sinus, a 51-year-old male patient with four months history of right cheek swelling and unilateral nasal obstruction, who underwent an operation and postoperative radiotherapy. Clinical, pathological and surgical findings in this case are presented along with a brief discussion of literature.