There are many reasons why nasopharynx has sticky phlegm, such as sinusitis, rhinitis, nasopharyngitis, reflux pharyngitis acid reflux and so on. 1. Sinusitis: Sinusitis is caused by microbial infections, which can lead to the phenomenon of mucous phlegm in the nasopharynx, accompanied by nasal congestion, runny nose and other phenomena. 2. Rhinitis: Rhinitis can lead to nasal mucosa congestion, swelling, oozing and other pathological phenomena, due to the increase in nasal secretions backflow to the throat, which will lead to the phenomenon of mucous phlegm spit in the nasopharynx. 3. Nasopharyngitis: Nasopharyngitis is an inflammation of the nasal cavity and throat, due to the increase in secretion caused by inflammation stimulation, which will cause the phenomenon of mucous phlegm spitting in the nasopharynx. 4. Reflux pharyngitis acid reflux: stomach acid reflux to the throat, will also show the phenomenon of mucus in the throat, at the same time there can be bloating, belching (burping), acid reflux and other phenomena. There are many reasons that lead to mucus phlegm in the nasopharynx, after the symptoms, we suggest that patients go to the hospital in time to improve the examination, clear diagnosis, and take standardized treatment according to the doctor’s instructions.