Hawza ilmiyya is a seminary of traditional Islamic school of higher learning. Although it is a term used mostly by the Shi'a Muslims communities and refers to a traditional Shi'a centre where clerics are trained, another branch of Islam, Sunnism has its own schools and they are called Hawza ,too. The entities in Najaf, Iraq and Qom, Iran, are the preeminent seminary centers for the training of Shi'a clergymen. However, several smaller hawzas exist in other cities around the world, such as at Karbala in Iraq, Isfahan and Mashhad in Iran,India, Africa, Europe and North America. Students who apply for these centers are either graduated from ordinary schools or colleges, or just have passed primary years of ordinary schools, and haven’t gotten diploma. An exam and interview divides each group of them according to their grades. Then a center will be specified for them. After that, they reside in school and begin their studies. Students will be trained through years of studying classic texts in their original languages. Besides having to study "classics"which are standard Arabic texts in each subject area, that all Hawza students are expected to study, each Hawza tends to create its own syllabus, too. The studies will begin by learning fiqh, kalam, hadith, tafsir, philosophy, natural and abstract sciences as well as Arabic and Arabic literature. Once these studies have been completed, they may begin preparation to become a mujtahid by studying advanced ancient textbooks known as sat'h, and research courses known as kharij. Some students study as a registered student at a school, others are independent students who pick their own tutors and study at their own pace. Furthermore, a lot of students will engage in other Islamic activities during their studies, such as writing, translating, preaching, teaching others, etc. all of which could lengthen the duration of one's study. Most Hawza students consider themselves students for life. From the very first century of Isalm’s emerge ,this educational entity was held in Najaf, Baghdad and Halab. After the entrance of Islam into Iran a Howze was held in Qum.Gradualy other centers appeared in different cities of Iran. They sustained and growed throughout 14 centuries and different sovereignty. By Islamic revolution in Iran in 1978, these centers which had played a significant role in the revolution strengthened their roots in the basis of Iran’s society and even broadened their influences beyond borders more than ever. Today, Howze elmiye Qom is claimed to be the greatest Howze in all Shiite world. Since the establishment of the Islamic Republic,Shiite clerics have played an important political role in the state, government and society. Since then These centers have become institutions of the reproduction not only of the religious elites but also of political elites.Even the Constitution of Islamic Republic underlined their function in the structure of government. For instance, It implies that the head of Judiciary system must be a qualified clergyman called “Mojtahed” which will be selected by the Leader which is a Mojtahed too. Throughout the years after revolution, clergymen occupied a wide range of high ranking positions in Iran’s society.Therefore, their influence on diverse aspects of Iraninan everyday life is clearly detectable and cannot be ignored.