Bumps under the tongue in children can be caused by oral mucous gland cysts, sublingual gland cysts, oral ulcers and other factors. 1. Oral mucous gland cysts: oral mucous gland cysts can be triggered by oral trauma and other factors, the cysts are usually about the size of a soybean, usually not accompanied by pain and other uncomfortable symptoms, which can be manifested as lumps under the tongue. 2. Sublingual gland cysts: Sublingual gland cysts are mainly caused by factors such as broken glands or blockage of the distal end of the gland ducts, and usually have no obvious symptoms, but children can have pimples under the tongue. 3. Oral ulcers: due to malnutrition and local trauma, oral ulcers can be triggered, oral ulcers have a high incidence, ulcers can be round or oval, can be manifested as a child’s tongue under the pimples, in addition can be accompanied by severe pain, low-grade fever and other uncomfortable symptoms. Children with bumps under the tongue should consult a doctor in a timely manner, under the guidance of a specialist to actively carry out appropriate treatment, which will help to relieve the discomfort symptoms as soon as possible.