Nose odor is commonly caused by bacterial or fungal infection, may also be caused by nasal malignant tumors, it is recommended to ENT active diagnosis and treatment. 1. Infection: when there is sinusitis, chronic rhinitis, there is a large number of anaerobic bacteria reproduction and purulent secretion, can cause the nasal cavity can appear odor. If there is a large amount of secretion or fungal mass in the nasal cavity, it is necessary to clean the nasal cavity and treat with medicine. 2. Malignant tumor: malignant tumors in the nose include nasopharyngeal carcinoma, sinus carcinoma, etc., which manifests nosebleed, nasal congestion, headache, foul smell, etc., and should be treated by surgical resection. When there is foul smell in the nose, avoid using drugs blindly by oneself, and should consult doctor in time for clear diagnosis and standardized treatment.