Despite the visual and structural integration that characterizes Islamic architecture, reflecting religious and cultural values, the expressive relationship between form and structure has not yet been systematically studied in a comprehensive manner that reveals its symbolic, functional, and aesthetic dimensions. Hence, a research problem arose in the absence of a theoretical framework that interprets this relationship as a single unit that conveys meaning and embodies identity. Therefore, this is research aiming to analyze the expressive relationship between form and structure in Islamic architecture, using the Al-Mustansiriya School as a model to uncover the mechanisms that enable form and structure to work in tandem to produce an authentic aesthetic-symbolic discourse. The research hypothesis is based on the premise that architectural expressiveness in Islamic architecture arises from an inseparable integration between form and structure, such that aesthetic performance is linked to the effectiveness of the structural system. The research relied on the dual analytical approach between descriptive-theoretical and structural analysis using the ETABS program to evaluate the efficiency of the structural elements and their consistency with the architectural expression. The results concluded that Al-Mustansiriya School embodies an organic integration between beauty and structure, where structural elements, such as arches and walls, show both a functional and aesthetic role. Some elements were emptied of their structural function and transformed into symbolic.