Qajar architecture is considered as the historic season of Iranian architecture regarding the separation from the past traditions and keep pace with the achievements of the Western civilization. Qajar palaces, as the most progressive architectural works to attract the transformations of architecture in their era, played a vital role to change the values of Iranian architecture. This article investigates the tendency towards the Western architecture in palaces of Qajar Era and is looking for to evaluate the quiddity of this tendency from a critical view. The method in this research is case studies and combined strategies and the data collection has been prepared through the literature review and fieldwork. Research findings show that Qajar government did not have significant emphasis on gaining the technological and structural advances of the West and Qajar kings were limited and satisfied with superficial shifts to cover the weaknesses of their government. This approach, which rose to its peak at the late Naserid period, without having any concern for the evolution of the ancient patterns of Iranian architecture, finally weakened historical architectural traditions and caused to appearance of the completely alien and unfamiliar royal palaces in Iran.