Measuring the effectiveness of internal audit in public sector and the municipalities of an application on

he country and company bankrupties occuring in the world recently has put world and country economies into a difficult position. These developments have increased the importance of accounting and auditing more. As a result, the issues of evaluating current financial conditions, measuring the effectiveness of internal auditing and enhancing internal auditing system have become important considerations for each country.The thing to measure the effectiveness of the interal control is the internal auditing unit. The internal auditing plays an important role both for Turkey, for transparency in public administration and joining the European Union. The enactment of 5018 numbered law is an important step for adopting internal auditing in Turkey.When we ake into account that the assigning of internal auditors have being carried out since 2006 and their trainings were completed in 2008, we reach the conclusion that internal auditing took actual effect in the public sector fairly as from the year of 2009. As to today, some information has been started to be received in terms of which results could be obtained in the public sector by internal auditing.The thesis consists of four chapters. As to the implementation process of the studies, the measurement of internal auditing in the public sector was aimed at. For this reason, 110 auditors were asked to fill in a questionnaire consisting of 50 items. At the same time, some inputs and outputs regarding the activities of 18 municipalities have ben analysed via data envelopment analysis method by getting the them from the activity reports of the relevant municipalities and as a last step, the data received in this way has been interpreted.Keywords: Internal Control, Internal Control System, Effectiveness, Public Sector