The Loreta Square was founded during construction of the Czernin Palace, which had closed it completely in the western side. Name of the square settled in the first half of 18th century.

Its northern border is formed by a single-nave church of the Virgin Mary Angelic with a cloister of the Franciscan Order and a large garden. The building complex with some yards was constructed in 1600-1602 in the style of simple Franciscan architecture. A covered suspended passageway connects the cloister with Loreta. It is the oldest Franciscan cloister in Bohemia.

Prevailing part of the eastern part of the square is taken by the building complex of Loreta, constructed mainly at the financial expenses of the Lobkowitz family. Central part of the building, a Holy Hut, rose during 1626-1631 under command of builder Giovanni Battista Orsi. Ambits were built progressively since 1661, the storey was added around 1740 and a renowned treasury was established there. The main front into the square was reconstructed in 1720-1722 according to designs by Kilián Ignác Dientzenhofer. In the tower there were placed peal by clockmaker Petr Neumann from 1694, which plays the Marian Song.

The baroque building of the Czernin Palace turns into the Loreta Square with its monumental front. The builders were three generations of the count family of the Czernins of Chudenice. The basic project was elaborated by arch. Francesco Caratti. In the course of time also others were participating, including significant artists. The last huge reconstruction proceeded during 1929-1934 under command of arch. Pavel Janák, when the palace was adjusted for the needs of Ministry of Foreign Affairs of ČSR.

On 16th May 2005 a sculpture of the previous president of the Czech Republic, Edvard Beneš, was unveiled in the square area. It was made by casting the original by Karel Dvořák.