The castle of Qajari villages in Dinavar region in Kermanshah province is among the ancient remains that reflect the political and social evolutions and architectural developments of this period. During this period, castles remained in the context of some villages in the region, which can be considered as residential castles belonging to the khan/lord in each village, which have the same plan and components. The aim of this research is to study a castle from the Qajar period in the village of Karaj in the Dinavar region and compare them with other contemporary castles. This research is a descriptive-analytical method and by conducting field and library studies, it intends to study the common architectural pattern for building a castle in some villages of Dinavar region in the Qajar period. The main questions in this article are: 1. What does the abundance of rural castles in the west of the country have to do with the social and economic conditions of the Qajar period? 2. What kind of spatial and plan structure do the castles of Karaj village belonging to the Qajar period in the Dinavar region follow, and in what other areas can similar examples be seen? The results show that such rural castles as lordly houses belonged to the Khan of each village or region, which were built for social and economic reasons such as agriculture and taxation with square plans and four circular towers in the corners of the building. Based on preliminary studies, it can be said that similar examples of this type of plan can be seen from different regions of Kermanshah, Ilam, Lorestan and Dehloran provinces in the Qajar period.