Environmental issues and energy crisis are among the problems of contemporary man for which the local architecture in hot and arid areas in Iran has offered some wise solutions. This kind of architecture could obtain great success in thermal balancing with the help of suitable materials and knowledge of the local architects. That is why recognizing the patterns of this architecture can be useful for designing modern houses. This research studies the structural components of Yazd Qajar houses in the hot and arid areas of Iran. The statistical population of this study contains ten traditional houses in Qajar era because most of these buildings have been built in this period. The main objective of this research is recognizing the structural components of the vernacular houses in hot and arid areas in Iran.The main questions are about the ways the structural components of this area could reach to a climatic accordance. The correlation method has been used for finding the relations between different spaces and geometric patterns. Data analysis and achieving to the conclusions have been done by comparison and induction. After doing field studies and collecting data, the measured dimensions of the structural components have been presented in different tables. The design standards used by traditional architects and also the structural patterns have been surveyed.The proportions and spatial relations between various areas have been investigated. According to the aim, this is a quantitative-qualitative research.The correct proportions of the structural components in hot and arid areas in Iran have been reported. This study pointed out that this kind of architecture (in its entirety and details) is in harmony with climatic conditions. Obtained results indicated that these traditional houses could provide the comfort of the residents. The results of this research show the success of traditional architects in reducing consumption of energy