Introduction: Tongue lesions are categorized into congenital and acquired classes. Accordingly, macroglossia, lingual thyroid, microglossia, and lingual tonsil are considered congenital lesions, and geographic tongue, fissured tongue, currugated tongue, median rhomboid glossitis, hairy tongue, benign and malignant tumors, ulcers, and white and red lesions are regsraded as acquired lesions. The identification of these cases and determination of their prevalence can be used to treat and relieve anxiety. Therefore, due to the high diversity of geographical distribution of tongue lesions, the aim of this study was to determine the frequency of tongue lesions among students in Sari, Iran. Materials and Methods: This descriptive cross-sectional study was performed on 540 high school students of Sari in 2019. The tongue surfaces were thoroughly examined by an oral medicine specialist. The tongue lesions, such as macroglossia, lingual thyroid, microglossia, lingual tonsil, geographic tongue, fissured tongue, corrugated tongue, median rhomboid glossitis, hairy tongue, and white and red lesions, were recorded in this study. The data were analyzed using SPSS software (version 16). Results: The obtained findings of the present study indicated that a total of 540 high school students (i. e., 270 females and 270 males) participated in this study. A coated tongue was observed in 33. 3% of the study subjects. Moreover, the lesions, such as microglossia, exophytic lesions, and median rhomboid glossitis, were present in 0. 2% of the patients. No ulcer was observed in any of the studied subjects. There was a significant relationship only between a hairy tongue (P=0. 004) and gender. The frequencies of other lesions were not significant between the two genders (P<0. 05). Conclusion: A coated tongue was reported with the highest frequency. In addition, the lesions, such as microglossia, exophytic lesions, and median rhomboid glossitis, were observed with the lowest frequencies. The frequencies of most lesions were not significant between the two genders. A coated tongue, fissured tongue, hairy tongue, and pigmentation lesions were significantly observed in male participants.