There will be blood in the nose, indicating a small amount of nosebleed, which may be caused by bad habits, trauma, rhinitis, nasal sinus tumor and other factors. 1. Bad habits: the existence of the bad habit of picking the nose with the hand may lead to frequent breakage of the nasal mucous membrane bleeding, which will cause blood in the nose, improve the bad habits can be improved on their own, will not cause too much impact. 2. Trauma: nose area suffered trauma, such as external blows, may make the local capillary rupture bleeding in the nose, will lead to blood in the nose, may also be accompanied by swelling, pain and other symptoms. 3. Rhinitis: such as acute rhinitis, atrophic rhinitis, etc., may lead to blood in the nose, which may be accompanied by nasal congestion, runny nose, decreased sense of smell, headache and other symptoms. 4. Nasal sinus tumor: for example, nasal septum capillary hemangioma, nasal sinus malignant tumor, etc., after the necrosis of tumor surface tissues, it will cause nosebleed, which may be accompanied by nasal congestion, olfactory impairment and other symptoms. It is recommended to consult a doctor for examination and treatment of blood in the nose.