Lattice structures have recently gained significant attention in research due to their excellent mechanical properties relative to their density and their high tunability through various design parameters. This study aims to investigate the effect of increasing the unit cell aspect ratio in the loading direction on the compressive properties of body-centered cubic (BCC)-based lattice structures. Compression tests were performed on both the base material and lattice structures with four different aspect ratios. In addition, tensile tests were conducted on the base material. The results show that Young’s modulus, yield stress, and peak stress increase linearly with aspect ratio. Structures with higher aspect ratios are stiffer and can carry more load, but exhibit lower energy absorption. The findings confirm that a wide range of mechanical responses can be achieved. This study demonstrates that the aspect ratio can be effectively used as a design parameter for tuning mechanical properties while maintaining a constant relative density.