The role of the prosecutor in criminal detention is one of the important and controversial issues. Accordingly, the purpose of this article is to examine the question of what role does the prosecutor's office play in the management of criminal prosecution in Iran and the United States of America? The present article is descriptive and analytical and has investigated the mentioned question by using the library method. The findings indicate that the prosecutor's office in Iran is appointed and affiliated with the judiciary, while in the United States it is elective and affiliated with the executive branch. In both legal systems, criminal prosecution is managed by the prosecutor's office; With the difference that in America, by accepting the principle of having the status of prosecution, the prosecutor's office has wider powers in the management of criminal prosecution. Trimming the prosecutor's office in Iran and transforming this institution into a strong and efficient management of criminal prosecution requires that, first of all, While in the American legal system, the focus of prosecutors is on the management of criminal prosecution and the society is sensitive to the performance of the prosecution in the management of criminal prosecution and as a result of correcting the wrong procedures of the prosecution institution, it has become the desire and demand of the society regarding the correction of wrong procedures in the case of the prosecution. There is no such demand in Iran.