Nowadays, environmental aspects play a significant role in the research, development, and application of technological solutions within the automotive sector. Thereby, automotive lightweight components, leading to less material consumption and, therefore, reduced manufacturing and operating environmental impacts, are considered a key factor for sustainable and resource-efficient mobility. Recently, a particular focus has been given to polymer multi-material lightweight structures. These have the potential to reduce environmental impacts throughout the entire life cycle of the materials compared to conventional monolithic aluminum or magnesium lightweight components. An example in this context is the construction and process development of functionalized multicomponent structures with complex-shaped hollow profiles (FuPro), combining fiber-reinforced thermoplastics, organic sheets, and injection molding. Furthermore, recyclability can be achieved using a single fiberglass-reinforced polymer (FRP) matrix and laser structuring processes for material bonding. However, to make an actual and measurable environmental contribution, potential hotspots of such lightweight structures and optimized manufacturing in terms of the lowest possible environmental impact must be assessed through a life cycle approach. Life Cycle Assessment (LCA) in the early stages of development has great potential to support decision-making processes. Yet, considering previous publications, it has only been carried out to a limited extent for automotive lightweight structures, posing new modeling challenges. Commonly, environmental impacts considering recyclability have not been clarified, and impact categories have mostly been limited to the Global Warming Potential (GWP). Thus, an LCA including the main phases of the process is contemplated following the ISO 14040/14044 standards. As a result, an LCA modeling framework for the recyclable multi-material lightweight structures, building on the FuPro process and determining the functional unit, the system boundaries, potential environmental impacts, and a broader range of impact categories, is proposed for assessing environmental hotspots and improvement potentials.