In diabetes mellitus there is an increase in blood glucose levels or hyperglycemia, which can cause several com- plications. Saliva is a body fluid that contains a variety of compounds produced by the salivary glands. Chronic hyperglycemia in diabetes mellitus is thought to affect salivary production. This study aims to determine the impact of diabetes mellitus on salivary contents. We collected articles from databases such as PubMed, Science Direct, and Google Scholar from 2014 to 2021. We found that there were salivary glands abnormalities that cause changes in the salivary contents. In saliva diabetic patients contain high levels of glucose, protein, alpha-2-macroglobulin, aspros- in, TGFβ-1, TNF-α, and high amount of Lactobacillus. Conversely, in saliva diabetic patients contain low levels of immunoglobulin A. We conclude that there are alteration in saliva contents in diabetic patients which could cause oral problems.