This study conducts experiments to assess the behavior of reinforced concrete (RC) beams using varying levels of fly ash (FA). Five beams were fabricated, each measuring 230 mm x 300 mm x 1600 mm. Four of these beams were grade M20 (28 days compressive strength equal to 20 MPa) reinforced concrete, with FA proportions of 0%. 5%, 20%, and 30%, while one beam was grade M25 with 20% FA.The M20 grade beam with 0% fly ash served as the control beam(CB). After a 28-day curing period, these beams were subjected to testing under a three-point bending system. Testing parameters included central displacement, failure load, and observation of failure mode and crack patterns. The performance of each type of reinforced concrete beam was compared to that of the control beams. The results revealed that the beam with 20% FA exhibited a comparable load-displacement behavior as compared to the control one making 20% FA an optimum dose of FA.