A substantial interest has been manifested in utilizing oil/metal oxide hybrid bionanocomposite, especially organic/ inorganic to design different biomedical applications. The present study reports the synthesis, characterization, antibacterial and anticancer properties of biogenic silver nanoparticles (AgNPs) and
L.satiVum
oil/PEG/Ag-MgO bionanocomposite. The fabricated AgNPs and
L.sativum
oil/PEG/Ag-MgO bionanocomposite were characterized by employing different spectroscopic (UV, FTIR, XRD) and microscopic (TEM, SEM) techniques. The particle size analysis showed that the mean size of 16.32 nm for AgNPS and 13.45 nm
L.satiVum
oil/PEG/Ag-MgO, indicating the excellent dispersion of Ag-MgO nanoparticles in the PEG–
L.satiVum
oil matrix. The antimicrobial activity of AgNPs and polymeric bionanocomposite was investigated against two pathogenic bacteria. The highest antibacterial effect was observed for bionanocomposite towards Gram-positive
Staphylococcus aureus
(27 mm) and Gram-negative
Escherichia coli
(25 mm) at 40 µg/well. The bionanocomposite completely vanished the bacterial growth (100%) at 80 µgmL
−1
concentrations. Moreover, the AgNPs and polymeric bionanocomposite was evaluated for anticancer activity against human cervical cancer cells (HeLa cells) at different doses (50, 250, 500, and 1000 µgmL
−1
). The results showed polymeric bionanocomposite was stronger in inducing the HeLa cancer cell death than AgNPs. Overall, the fabricated
L.satiVum
oil/PEG/Ag-MgO bionanocomposite serve as a potential antimicrobial and anticancer agent and could be used in the development of novel drugs and health care products in near future.