Magnesium oxide nanoparticles (MgO NPs) represent an interesting inorganic material widely utilized across various fields including sensing, antimicrobial applications, optical coatings, water purification, fuel additives, absorbents, and catalysis, owing to their exceptional broad energy band gap, surface affinity, and strong chemical and thermal durability. In this investigation, MgO NPs were successfully synthesized through a green approach employing fruit extract from the gingerbread tree (Hyphaene thebaica). Analysis via scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed their agglomerated quasi-spherical shape with a size range of 20-60nm. The X-ray diffraction (XRD) pattern exhibited prominent peaks at planes (200) and (220), indicating the high crystallinity of MgO NPs with a crystallite size of 32.6 ± 5nm while Energy-dispersive X-ray spectroscopy (EDS) analysis highlighted the composition comprises 40.47% Magnesium and 48.64% Oxygen by weight. Fourier transform infrared spectroscopy (FT-IR) revealed characteristic Mg-O bonds through peaks at 560cm-1 and 866cm-1, while Raman spectroscopy affirmed the cubic structure of MgO. Subsequently, the photocatalytic performance of MgO NPs under visible light irradiation was evaluated. Remarkably, the addition of 1g/L of MgO nano-catalyst resulted in a degradation efficiency of 98% after 110min on methylene blue dye, showcasing the high catalytic activity of MgO NPs. This remarkable photocatalytic efficiency emphasizes the potential of MgO NPs in environmental remediation.