Pain on the side of the tongue needs to be alerted to diseases such as oral herpes, burning mouth syndrome, tongue cancer, etc. It is necessary to go to the hospital to determine the cause of the disease based on oral clinical manifestations and laboratory tests. 1. Oral herpes. When the organism is infected by herpes virus, symptoms such as irritating pain, burning pain and itching may appear at the lesion site in the prodromal stage, followed by clusters of blisters and vesicles. Laboratory tests show the presence of viral particles. 2. Burning mouth syndrome. For menopausal women or long-term drug abusers who have pain on the side of tongue, they need to be alert to burning mouth syndrome. Oral examination usually has no lesions, but the tongue is painful with burning sensation. 3. Tongue cancer. Tongue side pain needs to be alert to tongue cancer, when the cancer presses the receptor block or invades the nerves, it can cause the pain on the edge of the tongue, and the tongue body can be touched with the hand to touch the nodule. It is recommended to go to the hospital in time to deal with the pain on the side of tongue to avoid damaging the oral health.