Abstract: This project investigates the structural behaviour of castellated steel beams through a combination of Finite Element Analysis (FEA) and software investigation. Castellated beams, known for their web openings, offer improved structural performance with reduced weight. The study focuses on the deflection patterns of these beams under various loading conditions. ANSYS software was used to model and analyse the beams, both with and without stiffeners around the openings. The results indicate that the incorporation of stiffeners significantly enhances the beams' strength and reduces deflection, optimizing material usage without compromising structural integrity. The strategic placement of stiffeners led to a substantial reduction in steel volume, demonstrating an efficient design approach that balances weight reduction and strength. This work underscores the importance of FEA in optimizing structural designs, providing valuable insights into the behaviour of castellated beams and promoting innovative solutions for industrial applications. The findings contribute to the broader understanding of steel beam behaviour under different loading conditions, highlighting the effectiveness of stiffeners in enhancing performance and efficiency in structural engineering