Among the many surviving architectural edifices of the pre-Safavid Islamic era in Iran, there are mainly the burial places, religious and public benefit buildings. However, as a matter of fact, throughout a time span of a thousand years, from the beginning of Islam until the Safavids, there is not a considerable number of palaces which belong to the pre-Safavid Iran. Therefore, the main questions here will be how the shape of the Iranian palace has been formed in this period of the Islamic era, and how their architectural and decorative characteristics were. Addressing these question could shed light on our understanding of the non-religious architecture during the Islamic times in Iran. To make this research as precise and limited as possible, investigations will be confined to the edifices belonging to the Ghaznavid period, because even though they were a dynasty of Turkic origin, their Capital, Ghazni was a center in which the Persian culture and language outshone. Therefore, due to the predominance of the Iranian culture, an authentic Iranian architecture could be sought for in this period. Hence, through studying the related works of scholars and the archeological findings of the excavation, we found no evidence of the mentioned palaces in Iran today; however, the studies suggest that within the cultural reach of Persia (Iran), the remains of the two Ghaznavid palaces in the modern day Afghanistan, have previously been excavated. Thus, studying the architectural and decorative features of these two palaces is the aim of this paper. In this manner, we could understand the architecture of the Iranian palace in this part of the Islamic era whose palatial architecture is not known enough; and also decide whether and to what extent they have been inspired by the Iranian Architecture, or if, as some western scholars have suggested, they were built with the influence of the Abbasid palaces of Samarra. The result of this study indicates that because of the four-Iwân plan in these buildings, this form of architecture has been used not only for the mosques, caravansaries and schools, but also in the palaces; in addition, they appears to have had precedence in terms of the construction time, over the other similar examples of four-portico buildings in Iran. Moreover, the comparative analysis between their characteristics and those of the older Sassanid instances as well as the palaces of Samarra, determines that apart from having been inspired by the pre-Islamic architecture of Iran, due to the predominant of Khorasani and Persian culture under the rule of Ghaznavids, the architectural style of the palace in this period has been completely Iranian.