This document summarizes a study on the effect of coconut shell particle loading on the flexural properties of coconut shell/cardanol resin composites. Composites with 0%, 10%, 20%, 30%, and 40% coconut shell particle loadings were created using compression molding. Testing found that the composite with 30% particle loading exhibited the highest flexural strength, 46% higher than the unreinforced resin. Scanning electron microscopy showed good particle-resin bonding and an absence of voids or cracks in the 30% composite. In contrast, the 40% composite exhibited cracks and voids, explaining its lower strength. Overall, coconut shell particles improved flexural properties up to 30% loading but higher loadings reduced properties