The City of Kashan is a rich source of historical houses dating back to Qajar Period, and the effect of social and cultural components on the formation of a spatial system in houses of Kashan is visible. Visual quality is one of the important qualitative features of the environment and particularly the residential space. The level and possibility of viewing are among the aspects of visual quality. In the current study, the visual field of ten types of houses in Kashan has been analyzed by placing the vertical visual field of the room on the yard as an index. In the first step, the houses fell under five categories, in terms of form and physical body: Houses with one yard surrounded by three volumes, with one yard surrounded by four volumes, with two yards surrounded by three volumes, with three yards surrounded by two volumes and with three yards surrounded by three volumes. In the second step, viewing angle of the observer while sitting was determined by Depthamp Software. Then to analyze the sight, in sitting position, in all types, the Space Syntax method and the Isovist analysis method were employed. In lines with this, the indexes of visual field (area, the amount of thrust angle, the maximum radius line and enclosure) in these houses were analyzed by software. The findings of the study show that there is a relationship between the ratio of width and height of openings and the depth of the yard. تفاصيل المقالة