To preserve valuable architectural works, the first step is to have a complete and comprehensive understanding of these works. Among the valuable parts of architectural works are their decorations and murals. Canvas murals are a type of mural that differs from regular and continuous murals in terms of materials, execution method, and generally in nature. Considering that the first step in preserving a work of art is its understanding and perception, the difference between these works is such that carrying out the usual methods of conservation and restoration (without a correct understanding of the work) will damage their authenticity and integrity. In the research conducted on the subject of canvas murals, some researchers place these works in the group of paintings on canvas, and some researchers also recognize these works as murals, and there is insufficient knowledge in this field. The restoration theories that have been presented and published at the national and international levels have references to the preservation and restoration of historical paintings, but they have not directly mentioned how to preserve and restore canvas murals. In order to reach the theoretical principles and foundations of the preservation and restoration of this type of murals, it is necessary to examine international charters, theories, and guidelines in the field of the preservation of historical paintings so that, according to these theories and also the studies that are carried out in the field of identifying the criteria for the preservation of canvas murals, it is possible to systematically recognize, restore, and display canvas murals correctly. In this article, the constituent layers of historical Iranian murals are first introduced, and then the results of the studies of written sources in the theoretical field of the restoration of historical paintings are presented. In fact, these studies and discussions are an introduction to the preservation and restoration of Iranian canvas murals.