The main causes of blisters on the tongue are the following: first, herpes virus infection leading to herpes stomatitis or herpes cheek infection, the virus causes dense patches of small blisters to appear on the tongue, mucous membranes inside the mouth and cheeks. Its small blisters are very thin, especially easy to break down, after breaking down, leaving red, swollen, congested, vesicular surface, seriously affect the diet and speech; second, due to the mouth with misaligned teeth, sharp tooth tips and bad restorations lead to frequent biting or scraping the tongue, resulting in traumatic blisters and blood blisters on the tongue, the need to adjust the grinding tip of the teeth to re-set dentures, if the blisters and blood blisters are relatively small, usually can be self-absorption, if the volume is relatively large Third, due to the lack of vitamin B and vitamin C in the body or due to immune dysfunction, resulting in ulcers on the tongue mucosa, lichen planus, white spots and a series of other mucosal diseases can also cause blisters on the tongue.