There is a lump inside the right cheek, which may be related to ulcerative hyperplasia of the right buccal mucosa, hyperplasia of the right parotid ductal papilla, and enlarged lymph nodes in the right cheek. 1. Ulcerative hyperplasia of the right buccal mucosa: when the right maxillary third molar erupts buccally, it often rubs the right buccal mucosa and produces ulcers, and prolonged non-healing of ulcers may be accompanied by localized hyperplasia, which may be manifested as a pimple inside the right cheek. 2. Right parotid duct papillary hyperplasia: the right parotid duct opening is in the buccal mucosa opposite to the crown of the right maxillary second molar, which is in the form of a papilla. When chewing food with bumps and bites, it can cause ulceration and hyperplasia of the opening papilla of the duct, which is manifested as a lump inside the right cheek. 3. Enlarged lymph nodes in the right cheek: there are lymph nodes under the mucous membrane and between the muscle tissues in the normal cheek, when there is apical inflammation, pericoronitis and periodontitis of the right side of the teeth in the mouth, the lymph nodes in the right side of the cheek can be enlarged, which will be manifested as a lump in the right cheek. There may be other causes of a lump inside the right cheek, should be timely consultation, improve the examination, clear diagnosis, standardized treatment under the guidance of a professional physician.