Due to the high number of lesions which can be found in children's oral mouths, it becomes really important to make a correct diagnosis in order to plan the right research and treatment. Appropriate diagnosis and management of these lesions in children require the knowledge of pediatric dentists of the frequency of such lesions and to distinguish which of them is caused, or associated, with a systemic disease. The aim of the study is to determine the prevalence of oral mucosal lesions in children. This is a retrospective study. All the data were taken from the patient archives of the dental institute. Children were in the age group of 5-17 years. A total of 1910 children were included in the study. All the necessary information was collected and entered in Microsoft Excel spreadsheet and subsequently transferred to SPSS version 23.0 for statistical analysis. Chi square tests were employed to find the association between different variables and p < 5% was considered statistically significant. The prevalence of oral mucosal lesions in children was found to be 5.44%. Males and females had an equal distribution of oral mucosal lesions of 0.37%. The 13 - 17 years age group had more mucosal lesions (2.53%). Among the gender and age groups different types of lesions were studied and it was found that aphthous ulcers are the highest which is 0.73% among gender and 0.45% among age groups. The dental professionals can educate the parents of the children about some common oral mucosal lesions so as to aid in the timely identification and treatment of the mucosal lesions.