Abstract:[Objective] Isolation of a bacterium strain named TZ-1 synthesized magnetic nano-particles from Dongchang Lake in Liaocheng City. [Methods] Proceed the morphological study and 16S rRNA gene identify to the strain TZ-1, extract and depurate the magnetic nano-particles form TZ-1 culture. Observe and analyze TZ-1 cells and the magnetic nano-particles through transmission electron microscope (TEM), scanning electron microscope (SEM) and X-ray diffraction (XRD). [Results] Concluded that TZ-1 belongs to Burkholderia sp.. The cells of TZ-1 is rod under the TEM, possess flagellum and capsule easy to gather. The approximate polygon in like electron dense granules arounded biomembrane in the cells include two types in size for 60 nm approximate located at the cytomembrane and 180 nm approximate located inner the middle of cells. The cells are rod under SEM, and the sizes are the same as the TEM. EDAX spectrum for the magnetic nano-particles on SEM shows that the main elements are Fe, P, O. According to the result of TEM, SEM and XRD that TZ-1 can compose magnetic nano-particles. [Conclusion] The bacterial strain TZ-1 we isolated synthesized magnetic nano-particles, XRD shows the ingredient of the magnetic nano-particles are Fe3(PO4)2·8H2O and Fe3O4, and the crystal structure of the magnetic nano-particles is monoclinic crystal.