This document presents a study on the flexural behavior of reinforced concrete (RC) beams with partial replacement of coarse aggregate by coconut shell. Twelve beam specimens of size 700 x 150 x 150 mm were cast using M20 and M30 grade concrete with 0-25% replacement of coarse aggregate by coconut shell. The specimens were tested after 28 days under two-point loading to determine the compressive and flexural strengths, which were then compared to a control concrete mix. Previous research on using coconut shell as aggregate in concrete is reviewed. The objectives of the study are to determine the optimum percentage of coarse aggregate that can be replaced, examine the feasibility of using coconut shell concrete, and encourage the use of coconut shells as a construction material.