Any spatial system, including rural settlements, is continuously and dynamically transforming from within and without under the influence of various and numerous factors (environmental, socio-economic, historical, and political). Among these, rural settlements located on the periphery of urban centers (especially metropolitan areas), which are constantly and directly exposed to the structural and functional characteristics of the city, are particularly and increasingly facing two main and fundamental types of challenges: on the one hand, the gradual erosion and disintegration of their authentic and traditional fabric and function, and on the other hand, the creation and formation of ambiguous and hybrid spaces that are neither urban nor rural. In reality, the ultimate result of these rapid changes and transformations is the disintegration and profound structural-functional rupture of the settlement system in these peri-urban spaces. Accordingly, the present research and study has been prepared and compiled with the main objective of understanding and analyzing the spatial metamorphoses of peri-urban rural settlements, with a special emphasis on the Shahriar district, over a ten-year period (2011-2021). The research method employed in this study is descriptive-analytical, and within this framework, all required data was collected and extracted from various sources. The results of the final data analysis using the Weighted Aggregated Sum Product Assessment (WASPAS) multi-criteria decision-making method in the Excel software environment clearly show that, out of the total 33 villages examined and analyzed, 14 villages have distinctly and significantly experienced more intense and greater spatial metamorphosis during this decade, which further reveals the necessity for targeted attention and management of these trends.