There are many reasons for pain at the root of the ear when eating, such as acute pharyngitis, temporomandibular joint dysfunction, ear inflammation and so on. 1. Acute pharyngitis: Acute pharyngitis can cause pain in the throat, and due to the stimulation when swallowing, it can cause the ear root to have the involvement pain of the glossopharyngeal nerve. 2. Temporomandibular joint dysfunction: Temporomandibular joint dysfunction can lead to facial muscle activity, involving the auriculotemporal nerve, which leads to pain in the root of the ear when eating. 3. Ear inflammation: Otitis externa, otitis media and other ear diseases can also lead to pain in the ear. There are many reasons that lead to pain in the root of the ear after eating, and after the symptoms appear, you should consult a doctor in time to clarify the diagnosis and cause of the disease, and do not ignore the symptoms, so as not to delay the treatment of the disease.