This work presented a green approach for the synthesis of hematite (α-Fe2O3) magnetic nanoparticles (MNPs) using the aqueous extract of Teucrium Polium plant. The aqueous extracts were prepared by the maceration and microwave-assisted extraction (MAE) techniques and performed as the natural precursor for one-step green synthesis of α-Fe2O3 MNPs, at room temperature. The as-prepared α-Fe2O3 MNPs were characterized by different techniques including UV-Vis absorption spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray(EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and vibrating sampling magnetometer (VSM). The XRD results confirmed the high crystalline structure of magnetic α-Fe2O3 MNPs. The average particle size of MNPs was obtained around 60 nm. In addition, the antibacterial properties of the as-synthesized α-Fe2O3 MNPs against various pathogenic bacteria were investigated by well-diffusion test. Based on the observations, α-Fe2O3 MNPs were more sensitive against Gram-negative bacteria than the Gram-positive bacteria. Moreover, the DNA cleavage potential of the samples was studied, too.