목적: Sinonasal inverted papilloma (IP) is benign tumor of epithelial origin and has possibility of malignant transformation. We wanted to evaluate comparative features of sinonasal squamous cell carcinoma (SqCC) with IP and SqCC without IP 방법:We retrospectively reviewed 93 patients with sinonasal SqCC who visited Asan Medical Center from January 1997 to December 2014. 6We compared locatiation of tumor, stages of cancer, survival rate and prognostic factors. Differences in survival were compared using Kaplan Meier analysis and prognostic factors using Cox-proportional hazard model. 60 patents were sinonasal SqCC (Group A), 33 patients were sinonasal SqCC with IP (Group B) 결과:Mean age was younger in group A than group B, but there were no significant difference (59.2 vs. 61.4 years). In both group, the most common location of tumor was maxillary sinus (17 <51.5%>) vs. 46 <76.7%>) followed by nasal cavity (6 <18.2%> vs. 9 <15.0%>), ethmoid sinus (6 <18.2%> vs. 4 <6.7%>) maxillary sinus. Stage IV patients were more frequent in group B, significantly (11 <33.3%> vs. 31 <53.3%>, P = 0.03). Two-year survival rate was 64.4% in group A and 50.9% in group B. On multivariate analysis, existence of IP was the only prognostic factor of survival and odds ratio was 5.27 (P < 0.005). 결론:SqCC patient with IP has batter survival rate than SqCC patient without IP. Combined with IP was the only meaningful prognostic factor in survival rate.