There are several possible causes for red dots on the tongue. 1, it may be inflammation of the tongue papillae, the tongue is divided into filiform papillae, fungiform papillae, lobe papillae and contour papillae, such tongue papillae are distributed on the surface of the tongue, when red dots appear it may be due to inflammation of the tongue papillae, resulting in increased redness. 2, red dots on the tongue may be a sign of impending herpes of the tongue, red dots on the tongue, slowly foaming and small blisters appear. 3, red dots on the tongue may also be a sign of impending herpes of the tongue. This is caused by the herpes virus and usually requires antiviral treatment. 3, red dots on the tongue may also be a sign of an impending tongue ulcer, which is usually red at the edges and white in the middle, and will appear red, yellow and sore.