This study aimed to investigate the impact of the proportion of glass and Kevlar fibers in epoxy composites on their mechanical properties. To achieve this, we employed different combinations of layer counts, non-impregnated fiber mass, and reinforcing materials to fabricate the specimens. As a result, specimens with varying thicknesses and total composite mass were generated, thereby altering the volume fraction accordingly. The specimens made use of fiber glass and Kevlar, which were prepared through the vacuum banging technique with epoxy resin serving as the matrix material. Subsequently, the mechanical characteristics of the specimens were evaluated through uniaxial tension and three-point bending tests, focusing on stiffness and strength. It was observed that factors such as the number of layers, fiber properties, sample thickness, and mass of fibers and the overall composite played a significant role in designing a composite that exhibits optimized stiffness or strength-to-weight ratio.