The importance of the prosecutor in prosecuting of crimes and its close association with legitimate rights and freedoms has led to different approaches to the selection of this office. In legal systems, four methods are used for select prosecutor:  private; appointive; elective and combining/merit selection.The Iranian legal system has always and only experienced the methodof appointment; But elective selection has been used in most US states. Despite the benefits of this method, such as the proximity to democratic principles, it is essential to examine the challenges and potential pitfalls of this approach.Given the basics and experience of using the method in the United States, two category of challenges can be identified:First, the political and social challenges (theoretical) include:be affected of elected prosecutor by political authorities and emersion of criminal populism.Second, executive challenges include: limited legal procedures for accountability, inadequate selection criteria for citizens, few electoral rivals, modest changes in prosecutor's office, and neglectingideology of electoral candidates.