Congregational Mosque of Isfahan was founded in the North-west corner of "Kohneh-Square" (Old Square) and is the joint and converting point of old quarters of Dardasht, Abu-Eshaqieh, Nezamieh and Juibareh. It is the terminal of ancient Bazaar, with 6 km length. The initial mosque had been built adjacent to "Yaran" old village on Zoroastrian temple, belonging to pre-Islamic period.

City of Isfahan comprised of a number of spreading villages before Islam. Islam was accepted in 646 AD by its inhabitants. First mosque was built on the present site in 8th century AD. Due to expansion of the city and increase of the population, bigger mosque was founded on the initial in 10th century AD.

The mosque was subjected to certain changes with the objective of expansion and beautification in Al-Bouyeh dynasty period (10th century AD). During 11th century AD, the mosque witnessed biggest changes, both from internal and external aspects. In Seljuk period, a rotunda was added to the mosque and interior design was changed from nave to square verandas. This style of architecture (square verandas) remained in the history of architecture of Iranian mosques.

During Ilkhanian, Al-Mozaffar and Tymurid dynasties, appropriate opportunities existed for further architectural and ornamental developments in the mosque, as blind arcades around the courtyard, which were founded in two arcading with tile facade.

In 16th century AD, Safavid era, Congregational Mosque of Isfahan, which due to the violent political and population fluctuation had been subjected to stagnation, was again repaired and beautified.

The most important architectural order applied in the mosque, relates to Seljuk period, is Razi order. In this order, application of bricks and creation of brick facades, with tie design, is in its utmost expertise and beauty apparent. Internal and external facades of "Nezamol-molk" and "Tajol-molk" cupola are vivid example of this style.

Ornaments of walls are highly varied and picturesque. Plasterwork of "Eljaytou Prayer Niche", tile ornaments, masonry lines and different honeycomb works of verandas, along with Kufic and Thulth, interest in exultation of the mosque building.

Architectural style of winter and summer prayer halls, situated in Western flank of the mosque, are superbly exquisite and skillful. In these architectural spaces, due to thickness of brick vaults, the exchange of temperature with outside space is quite slow; so that, during winter period, the temperature inside is quite warm and in summer is quite cool.

In Al-Mozaffar period, a school was founded in Eastern flank of the mosque. It was destroyed during the historical upheavals; later, part of this was subjected to renewal.

The history of Congregational Mosque could be regarded as the history of the city of Isfahan. Mosque was founded contemporaneously with the foundation of the city. Later changes in the form and skeleton of the mosque are reflections of the political and social events of the city. The fire in mosque and library during Seljuk era and bombardment of South-western section during Iran-Iraq war are among mentionable events of its history.