Here's a better link for you:
Article 1
The form of government of Iran is that of an Islamic Republic, endorsed by the people of Iran on the basis of their longstanding belief in the sovereignty of truth and Qur'anic justice, in the referendum of Farwardin 9 and 10 in the year 1358 of the solar Islamic calendar, corresponding to Jamadi al-'Awwal 1 and 2 in the year 1399 of the lunar Islamic calendar (March 29 and 30, 1979], through the affirmative vote of a majority of 98.2% of eligible voters, held after the victorious Islamic Revolution led by the eminent marji' al-taqlid, Ayatullah al-Uzma Imam Khumayni.
Article 2
The Islamic Republic is a system based on belief in:
1.the One God (as stated in the phrase "There is no god except Allah"), His exclusive sovereignty and the right to legislate, and the necessity of submission to His commands;
2.Divine revelation and its fundamental role in setting forth the laws;
3.the return to God in the Hereafter, and the constructive role of this belief in the course of man's ascent towards God;
4.the justice of God in creation and legislation;
5.continuous leadership (imamah) and perpetual guidance, and its fundamental role in ensuring the uninterrupted process of the revolution of Islam;
6.the exalted dignity and value of man, and his freedom coupled with responsibility before God; in which equity, justice, political, economic, social, and cultural independence, and national solidarity are secured by recourse to:
1.continuous ijtihad of the fuqaha' possessing necessary qualifications, exercised on the basis off the Qur'an and the Sunnah of the Ma'sumun, upon all of whom be peace;
2.sciences and arts and the most advanced results of human experience, together with the effort to advance them further;
3.negation of all forms of oppression, both the infliction of and the submission to it, and of dominance, both its imposition and its acceptance.
Iranian Goverment Constitution, English Text