Nasal boogers are many and yellow and easily crusted may be atrophic rhinitis, cold or nasal vestibulitis and other causes. 1. Atrophic rhinitis: atrophy of nasal mucosa, glands and turbinate bone, ciliated columnar epithelium becomes squamous epithelium, and crusts are infected by smelly nose bacillus. 2. Colds: viral infection can cause colds. When secondary bacterial infection occurs, purulent secretion is produced, and scabs are formed after pus accumulation. 3. Nasal vestibulitis: Repeated pus flow from the nasal area can cause nasal vestibulitis. This disease will affect the normal cleaning function of the nasal cavity, and by the inflammation stimulation, the nasal cavity will secrete purulent secretions, can appear boogers and yellow easily crusted symptoms. The boogers are yellow and easily crusted and may be caused by allergic rhinitis or malignant tumors of the nasal cavity and sinuses, etc. It is recommended that the patient go to the hospital in time to get a clear diagnosis.