Given the small number of historical Qajar houses remaining and the lack of in-depth studies on them, it is essential to understand the architecture of these historical houses, including those in the city of Shoushtar. Therefore, this article examines what characteristic spaces the main facades of Shoushtar houses have and what types emerge from their placement together on each Front? The aim of this article is to understand the main facades of Shoushtar houses that were built during the Qajar period. The research uses a qualitative approach and a historical interpretation method to understand the historical houses of Shoushtar. Then, the causes of the formation of the main Fronts of Shoushtar houses are examined from three perspectives: natural, environmental, and religious. The collection method was field and documentary. Among the 25 houses identified, 19 houses were selected as study samples, with the criterion of least interference in the main parts of the houses. The research findings show that the houses have different types on each front, which are built in an introverted and semi-introverted manner in a general system and based on their location in the historical context and its border with the river. Also, the division of the house space along the Koh- Qebleh axis into two mountain and Qebali sections, which creates a new axis in the form of a landscape, for visual openness to the outside of the house (river).