Sinusitis mouth bitter, because the sinus inflammatory secretions through the nasal cavity backflow into the oral cavity, stimulating the oral mucosa. Infection by pathogenic microorganisms such as bacteria, viruses and fungi when the body’s resistance is low causes lesions such as inflammatory exudation, bleeding and even suppuration of the sinus mucosal tissues. The secretion in the sinuses increases continuously, exceeds the capacity of the sinuses and flows into the nasal cavity, and backs up into the oral cavity through the nasal cavity, stimulating the oral mucosa and mouth bitter. Frequent contact with pollen and other allergens, smoking, poor air quality, malnutrition, cold and overwork and other conditions can easily induce sinusitis, nasal congestion, headache, pus flow, loss of smell, fatigue, memory loss and other symptoms. Sinusitis patients, should follow the doctor’s instructions standardized treatment, to avoid recurrence of the disease or cause other complications.