Abstract: Objective:To analyze the clinical features, diagnostic management and prognosis of primary ethmoid sinus malignant tumor in order to diagnose it earlier and treat it correctly.Methods:Clinical data from 22patients with primary eth -moid sinus malignancy treated in our hospital between January1984and December 2004were reviewed. All follow-up da -ta was completely attained and recorded. Gender, age, clinical stage, pathological type, treatment method and survival da -ta were analyzed respectively. Survival analysis was conducted with Kaplan-Meier method and Log-rank test was used to compare the survival rates. Univariate and multivariate factors for survival were analyzed by Cox proportional hazards re-gression model.Results: There were12male and10female patients, aged from 10to 72years, with an average of 42. Ten cases were diagnosed as squamous cell carcinoma and the other 12cases were diagnosed as other pathological types. The average follow-up time was 43 months (5~108 months). The overall 1-year, 3-year and 5-year survival rates were 70.2%,54.0% and 32.4% respectively. Univariate analysis showed that clinical stage (P = 0.045 ) and treatment ( P = 0.026 ) were prognostic factors. The 5-year survival rate of squamous cell carcinoma was not significantly different compared with other less common histological types (P = 0.4). Conclusion:The incidence of primary ethmoid sinus malignant tumor is low; and its diagnosis relies mainly on CT scan and postoperative pathology due to the lack of specific clinical features. Squa-mous cell carcinoma is the most common pathological type. Main factors affecting the prognosis are clinical stages and treatment. Surgery plus radiotherapy is the best treatment choice.