Gelatin used in the formation of scaffold is derived from fish-scales. Ulvan, a sulfated polysaccharide extracted from Ulva lactuca, was isolated using acidified hot water extraction method with a notable yield of 25.74%. The extracted ulvan was subjected to physical characterization through Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Thermogravimetric Analysis (TGA), while its chemical composition was confirmed by uronic acid determination. Ulvan was subsequently blended with marine-derived gelatin to fabricate bio-composite scaffolds aimed at tissue engineering applications. The scaffolds were evaluated for mechanical strength, thermal stability, porosity, water uptake capacity, and in vitro degradation profile. SEM analysis revealed a porous, interconnected microstructure favorable for cellular infiltration. The scaffolds demonstrated suitable physicochemical properties, including enhanced mechanical integrity and controlled biodegradability, indicating their potential for biomedical applications. This study highlights the promise of ulvan–gelatin scaffolds as a sustainable and functional biomaterial platform for regenerative medicine.