Hylite aluminum sheets are constructed from a combination of aluminum layers and a polymer core, commonly known as aluminum composite panels. These sheets consist of two thin aluminum layers on the outside, with a polymer core sandwiched in between. This multilayer composite structure imparts the sheets with characteristics such as lightness, high strength, appropriate impact resistance, and excellent formability. This study provides a comprehensive experimental analysis of the mechanical properties of AA5182 aluminum Hylite sandwich sheets with a polypropylene core, in comparison to monolithic AA5052 aluminum sheets. For this purpose, mechanical tests including uniaxial tension, in-plane shear, notched tension, and plane strain tension were conducted to evaluate performance in both conditions. The results indicated that Hylite sheets exhibited only a 19.6% reduction in load-bearing capacity under in-plane shear conditions, while under plane strain conditions this reduction reached 55.1%. Fracture observations revealed that under stress concentration conditions, Hylite sheets fail through shear failure and interlayer separation, rather than ductile fracture, leading to significantly lower energy absorption compared to monolithic aluminum. Furthermore, the present results show that increasing the thickness of the outer metal layers and reducing the thickness of the polymer core can noticeably enhance the mechanical performance of such sandwich structures. Although a significant reduction in maximum load capacity (55.1%) and absorbed energy (74.8%) was observed for the Hylite sheets compared to monolithic aluminum, the sandwich structure nevertheless exhibits a more favorable performance-to-weight ratio due to its lower weight (approximately 40%) and higher initial stiffness in tension.