Researching and recognizing the beliefs, convictions, environmental knowledge, techniques and traditional methods of each community allows us to know their interests. The purpose of this study is to document the native architecture of the inhabitants of Bahar city in order to record some parts of its unwritten history in addition to introducing it. This research has been done through observation, interview and participation. Shahr-e Bahar is located in the northwest of Hamadan and its inhabitants are from Baharloo tribe and they speak Turkish. The Baharlus came to this place from Central Anatolia in the 12th century and built the Bahar Fortress in the 13th century. Bahar Castle was destroyed by the Mongols in 1257. Therefore, some of the Baharlus came to the Bahar plain at least eight hundred years ago, and some of the tribes have remained in the Anatolian region. Bahar passed away and at the beginning of its formation, it was a village-castle. Gradually, with the development of the city, the first houses were built on the south side of the castle and near the qanats (aqueducts). There is now a castle neighborhood in the north of the city. The location of Bahar city in the northern part of Alvand Mountains has caused them to enjoy lush and productive ranges as well as temperate climate that tend to be cold and dry. By looking at the type of materials, the method of construction and the type of exploitation of spaces, we can understand the connection between man and nature. Also, the impact of livelihood and economy on the structure of the building and the function of the interior spaces of the houses is quite obvious. In compiling this article, it was necessary to translate local words and transliterate each word for careful reading. According to the results of this study, the indigenous residential spaces of Bahar have been used only for humans and animals and less attention has been paid to the aesthetic aspects inside and outside the building. For the past 50 years, due to population growth, lifestyle changes, the growth of mechanized agriculture, the ban on keeping livestock in the city, the tendency to build with new materials, the reshaping and function of house space, the construction of traditional houses are not common anymore. Today, houses are built in accordance with the economic function and social status of individuals and affected by urban life with minor changes in the location of services, health, storage and location of new rooms and home baths and the removal of some spaces such as kitchen, fodder warehouse, barn and home workshops. This article, tends to describe and analyze the status of indigenous residential spaces, the type of use and local terms with an anthropological appraoch. In order to better understand the relationship between the spaces and the time and type of exploitation, the occupational and social levels of the residents are introduced and the interior parts of the rooms and other existing spaces of the house are given along with the plan of the spaces. Housing is divided into four groups: ranchers, farmers, settlers, rancher-farmer. The main reliance of this study is on the dwellings of Qaleh neighborhood and besides that, the dwellings of other neighborhoods have also been studied. In the past, the main building materials were clay, thatch and wood, and only in some of the rich people’s houses’ entrance were decorated with a few bricks. But today, brick, cement and iron are the main building materials. It seems that with the vast changes that have taken place in the lifestyles of people living in urban, rural and nomadic communities, we will not see any signs of local and traditional architecture in a few decades. This article has been compiled from the point of view of an anthropologist and has not dealt with the technical issues of modern architecture. Today, the existence of old Bahar dwellings is threatened by the influx of urban culture and urbanization and new dwellings that have attracted the attention of its inhabitants. Therefore, accurate recording of all the details of this type of housing is being forgotten.