The tongue is able to quickly reflect the state of health or disease of the human body. Tongue inspection is an important diagnostic approach. It is a unique method that allows to explore the pathogenesis of diseases based on the guiding principles of the holistic concept that involves the observation of changes in the lining of the tongue in order to understand the physiological functions and pathological changes of the body. It is a potential method of screening and early detection of cancer. However, the subjective inspection of the tongue has a low reliability index, and therefore computerized systems of acquisition of diagnostic bioinformation have been developed to analyze the lining of the tongue. Next-generation sequencing technology is used to determine the V2–V4 hypervariable regions of 16S rRNA to study the microbiota. A lot of neoplasms are identified only at an advanced phase, while in the early stages, many subjects remain in an asymptomatic form. On the contrary, the early diagnosis is able to increase the prognosis of cancer and improve the survival rates of subjects. Evidently, it is necessary to develop new strategies in oral medicine for the early diagnosis of diseases, and the diagnosis of the tongue as a minimally invasive method is certainly one of them.