The paper examines all the extant sources (documents, narrative sources, the archaeological remnants etc), regarding the catholicon of Simonopetra monastery on Mount Athos. The research tries to suggest a highly probable hypothesis for the chronological phases of the monument, both for the construction (or reconstruction) and the painting. The changes in the church might have taken place in the late medieval and early modern period, beginning with the construction of the church by the Serbian despot Jovan Uglješa in the second half of 14th century. Three disastrous fires in 1580, 1622 and 1891 have heavily affected the history of the building. The recent restoration works reveal some pieces of wall-paintings, which help us to date a crucial phase for the history of the building in the second half of the 16th century.
