In this research, Ce_0.8Zr_0.2-xMn_xO₂ nano particles (x = 0.0, 0.05, 0.10) were synthesized at 600 calcination temperature by co-precipitation method. The starting materials were cerium and zirconium nitrates, manganese chloride and ammonia as a precipitating agent. The crystalline structure of the synthesized samples was studied by X-ray diffraction (XRD) technique. TEM images of the prepared Ce_0.8Zr_0.2O_2­ and Ce_0.8Zr_0.1Mn_0.1O₂ showed that their average particle size are about 8.2 and 7.3 nm, respectively. Fourier transform infrared (FTIR) spectroscopy was used to investigate the present bonds in the synthesized samples.