If patients get up in the morning with black sputum in the throat, the black component of the sputum may contain some old blood, which may come from the mucous membrane of the throat itself or from the nasal cavity, sinus, or nasopharynx area, as follows: 1. acute and chronic inflammatory diseases of the pharynx: lead to local mucous membrane rupture and a small amount of blood leakage, which is prone to accumulate gradually at night, and when they get up in the morning, they have black sputum. 2, Acute and chronic inflammatory diseases or abnormal growths in the nasal cavity, sinuses and nasopharynx: they also produce bloody secretions, which tend to flow backward into the pharynx and accumulate gradually in the pharynx, and also show similar symptoms, and further electronic nasopharyngoscopy is needed to help identify and diagnose them if necessary.