Objective To investigate the diagnosis and treatment of sinonasal hemorrhagic and necrotic polyps. Methods Clinical data of 93 patients suffering from sinonasal hemorrhagic and necrotic polyps during the period from 2002 to 2011 was analyzed retrospectively and its clinical characteristics, histological features, differential diagnosis and treatment were discussed in combination with review of the literatures. Results 93 patients were cured with endoscopic sinus surgery and the pathological diagnosis was made after operation. All the patients were followedup for 1 to 9 years postoperatively and none got recurrence. Conclusion Sinonasal hemorrhagic and necrotic polyp is a kind of special chronic inflammation characterized by hemorrhage and often clinically misdiagnosed. CT scanning of paranasal sinus is an effective way for diagnosis and endoscopic sinus surgery is the first choice for the treatment of this disease. To treat this disease successfully, the essential points are complete foci elimination and adequate ventilation and drainage of paranasal sinus.