In pursuit of environmental sustainability, polymers filled with bio-particulates are replacing traditional plastic components. Epoxy Polymer composites of eggshell powder were prepared at filler contents of 10 wt%, 20 wt%, 30 wt%. the particle size of the eggshell powder was 75 μm, 180 μm, and 250 μm. The composite samples were prepared using the Carver Inc. Hydraulic Press (3851-0) by compression molding and the resulting composites were produced in sheets. Some mechanical properties of the composite were determined. the result showed that the eggshell powder improved the tensile modulus, flexural strength and impact strength of the polymer these properties increased with increase in the filler content and decrease in the filler size. But at 30 wt% a decrease in these properties were observed which can be attributed to agglomeration and stress concentration effects. Highlighting the fact that the dispersion and distribution of filler particles within the matrix play a crucial role in determining the mechanical properties. Inhomogeneities in mixing or particle clustering could lead to variations in the measured properties.