The stir casting technique for producing aluminum metal matrix nanocomposites is commonly used for a variety of reasons, including its durability, simplicity, and cost-effectiveness. In order to fabricate a composite, aluminum A380 was taken as base material, and fly ash was used as a reinforcement in the fabrication of composite. As casting has influenced the environment by generating negative impacts since it has required huge amount of energy and materials. Therefore, in order to opt for the more sustainable practice of stir casting, it is important to consider its possible impacts on the life cycle. This paper consists of an environmental impact assessment linked with the fabrication of aluminum-based metal matrix nanocomposite through the stir casting process. In order to assess the ecological hotspots, an impact assessment “ReCiPe Endpoint” method was used. The outcomes reveal that huge amount of energy consumption during the melting phase is a major concern along with heat loss and it has major contribution toward environmental burden during the whole casting process. Moreover, the assessment results also indicated that this fabrication process has a highly negative impact on human health, which is justified by single score damage assessment result. Additionally, the study also highlighted that casting process has significant impact on mineral resource scarcity, freshwater ecotoxicity, marine ecotoxicity, and terrestrial ecotoxicity categories. Lessening the detrimental effects of the environment on human health may be achieved by switching from coal-based energy generation to renewable sources and utilizing innovative technologies in the area of raw material extraction.