Prince (Spătarul) Mihail Cantacuzino founded the monastery upon his return from a pilgrimage to Mount Sinai. The first buildings were completed between 1690 to 1695. It was designed to serve as a monastery as well as a fortified stronghold on the route from Brasov to Bucharest.
In the midst of the Russo–Turkish War, 1735–1739, before deserting the monastery, monks hid the valuables by burying them inside a bell. During a battle, the Turks defeated troops stationed within the walls of the monastery. The Ottomans burned the area and broke through the wall in two places.
Until 1850, Sinaia consisted of little more than the monastery and a group of huts. In 1864, however, the monastic estate was assigned to the Board of Civil Hospitals (Eforia Spitalelor Civile), which opened a hospital and several baths, and helped develop mineral springs in Sinaia.
Under the leadership of Hegumens Ioasaf and Paisie, construction of The Great Church began in 1842 using funds allocated by the monastery and was completed in 1846. This smaller structure was enlarged by the Board of Civil Hospitals during a period from 1897 to 1903. These efforts gave the building the appearance it has today.