Metal oxide nanostructures have lately sparked a lot of interest owing to their high stability. However, chemical synthesis of these compounds necessitates the use of costly, toxic, and hazardous chemicals. This study involves the biosynthesis of magnesium oxide nanostructures (Nano-MgO) using Beta vulgaris extract (BVE) as a reducing agent in a simple and environmentally friendly way. Preliminary investigations were used to assess the phytochemicals present in the prepared BVE. The synthesized nanostructures were characterized by UV visible spectroscopy, SEM-EDX, XRD, FTIR, TGA, and DSC. The Nano-MgO absorption peak was observed at a wavelength of 270 nm. SEM studies showed a mean particle size of about 36.28 nm and EDX analysis revealed the presence of magnesium and oxygen in weight percentages of 27% and 72% respectively. XRD demonstrated the crystalline and cubic nature of synthesized Nano-MgO. FTIR verified Nano-MgO vibrational frequency at 565.07 cm^-1. Antioxidant assay (ABTS) revealed that Nano-MgO exhibited higher antioxidant activity than BVE alone. Significant antibacterial effects were demonstrated by Nano-MgO, with a substantial inhibition zone against Escherichia coli (3.8 cm) Staphylococcus aureus (3.9 cm). The cytotoxic impact of Nano- MgO on PC-12 cell lines revealed the IC-50 value to be 30.94 μg/mL for 24 hours of incubation.