Primary trigeminal neuralgia is a functional disorder of the nervous system characterized by pain on one side of the face that occurs in middle-aged and elderly people. Typical trigeminal neuralgia is characterized by episodes of transient, severe, knife-like, pinprick-like or over-electric pain in one side of the trigeminal nerve distribution, which often comes and goes suddenly and lasts for several seconds to tens of seconds. Although this disease seriously affects the quality of life, it can be cured by drugs and surgery with better results. However, some patients are often encountered to be misdiagnosed clinically, which affects their correct treatment. For example, some patients were treated as toothache, and the pain still came on after several teeth were extracted, and the pain disappeared immediately after microvascular decompression was done after correct diagnosis. Therefore, the correct diagnosis of primary trigeminal neuralgia is very important, and I will briefly introduce several diseases that are easily confused with trigeminal neuralgia here. 1, secondary trigeminal neuralgia: secondary trigeminal neuralgia is often caused by intracranial tumors, vascular malformations, etc. CT or magnetic resonance examination can reveal lesions located in the pontocerebellar horn region. The pain often lasts for a long time and there is no obvious gap period, and neurological examination mostly has positive signs. Since the principles of treatment for secondary trigeminal neuralgia are different from those for primary, patients who encounter patients presenting with trigeminal neuralgia should undergo cranial MR examination to exclude intracranial organic lesions. 2. Migraine: unilateral headache caused by vasodilatation imbalance. Before the attack, there are mostly visual aura, such as vision shackles and black spots in front of the eyes; it is mostly pulsating throbbing pain or dull pain; it lasts for a long time, usually lasting for several hours, and some of them can be relieved for up to one day; vasoconstrictors (ergotamine drugs) are effective. 3, toothache: mostly due to inflammation, such as acute pulpitis, periodontitis, periapical inflammation, dental caries, etc.. It is usually persistent pain, with obvious onset at night, sensitive to hot and cold stimuli, pain mostly confined to the gums, no discharge-like pain, no trigger point, and painkillers are effective. Oral examination can find dental disease. 4.Glottopharyngeal neuralgia: the pain site is usually located at the root of tongue, pharynx, tonsils and external auditory canal; the trigger point is located at tonsil fossa and pharynx; pain can be relieved by anesthetizing the pharynx.