Throughout various historical periods, human societies have observed Religious Structures as significant cultural artifacts, which have endured as objective representations. This heritage, while being respectable for every nation and the followers of every religion, through the continuation and repetition of traditions and beliefs, is instructive and opens the way for other nations to find the culture of that nation. Several factors affect the formation of the architectural body of these buildings, the knowledge of which can help in the architectural design of contemporary identity-giving buildings. Therefore, the present study aims to investigate and analyze the architecture of Qajar period Religious buildings in Mazandaran and Gilan, to understand the causes of the formation of the architecture of these two types of buildings, with physical differences that can be generalized to all the Religious buildings of this region studied.The current research is descriptive and content analysis in nature. The method of collecting information is documentary and field so the most important tools for collection are library sources such as documents of the General Directorate of Cultural Heritage and field observation of the tombs of Mazandaran and the tombs of Gilan. is to identify and determine their general characteristics and design patterns. Statistical community, Qajar period ritual building in the northern region of the country; They include the Blessed tombs of Gilan Province and Saqanfars of Mazandaran Province. The samples were selected and analyzed based on the architectural characteristics. The statistical population of historical monuments of Gilan and Saqanfar of Mazandaran is four each; These buildings include 4 Saqanfar Kijatakiyeh, Ledar, Firouzjah, and Hamza-Kala-Shesh-Pol in Mazandaran and 4 mausoleums of Agha Sayyed Mohammad Yemeni, Chaharpadshah, Seyyed Musa Ibn-e Jaafar (AS), and Nasir Ali Kia Ibn-e Imam Musa Al Kazem (AS) in Gilan. The required information has been collected in documentary and field form and described and analyzed in a comparative context. The findings of the research indicate that the climate and consequently the native architecture of the region is the most important factor shaping the architecture of these two types of buildings. In the selection, it has been tried to ensure that the buildings are standing and are chosen with architectural differences so that they can be generalized to all the Religious buildings of this region in the Qajar period.In this research, the architecture of Qajar period Religious buildings in Mazandaran and Gilan, including four tombs and four Saqanfar, was investigated and analyzed to find the causes of their formation from the perspective of architectural features. For this purpose, the influence of history, climate, and ritual issues were investigated. In terms of historical period; The time frame of the creation of the paintings that were carved on the surface of the walls of the tombs of Gilan and the top of the wooden boards of the Saqanfars of Mazandaran, and the architecture of these two types of buildings were both during the Qajar period. The architecture of this period is derived from both Western and ancient Iranian architecture, indicating the absence of a specific architectural style in the buildings of this period, except for government buildings and palaces.From a local perspective, the Saqanfars were constructed in the Mazandaran region, and the tombs were built in the Gilan region. When examining the local architecture, it is evident that the climatic conditions, customs, and specific beliefs of each region have influenced the architecture of these two types. The influence of Religious beliefs is evident in the shrines and monuments built by humans to fulfill their Religious duties. The harmony of the facial, bodily, and structural aspects of the building in these regions can be understood in relation to the customs and Religious beliefs of the local people through these two building types.These types of buildings act as the identity card of the ethnicity and cultural identity of the people of that region, and sometimes in its formation, economic and social relations with the natural environment and cultural symbols, rituals, and beliefs of the people of the region are reflected. According to the analysis and investigation of the main factors of the use of each of the architectural elements in these two buildings, it can be said that the structural differences between these two types of Religious buildings are caused by the context in which these two types of buildings are built. Climate is the most significant reason for the difference in the architecture of these two types of buildings, and religion is second in importance.