Technological and financial developments experienced globally carry risks in many dimensions byforming complex structures, and these risks increase and pose a great threat to institutions. These risksare handled in the financial terms under the heading of accounting errors and frauds. Accounting errorsand tricks; These are transactions made without complying with accounting principles, standards andregulations. Erroneous and fraudulent transactions negatively affect the accuracy and reliability offinancial reports of institutions. The main purpose of the study is to determine the errors and fraudsarising from the accounting system in Metropolitan Municipalities, as institutions that use significantpublic resources, and to reveal their relationship with the components of the internal control system.In the study, errors and frauds arising from the accounting system were determined by applying thecontent analysis technique to the audit reports of the Court of Accounts of 6 Metropolitan Municipalitiesfor 2019. Evaluations were made according to the frequency of the identified errors and frauds, andthey were associated with the components of the internal control system. Thus, it was determinedrelationally what kind of errors and frauds occurred due to the inadequacy of which component ofthe internal control system of the Metropolitan Municipalities. Errors and frauds arising from theaccounting system in Metropolitan Municipalities are caused by inadequacies in the internal controlenvironment, control activities, information and communication components, respectively.