In this research, work nanopowders of Zn_1-xMn_xO (0.0) dilute magnetic semiconductor were prepared via sol-gel autocombustion method. The crystal structure and phase purity of samples were confirmed by X-ray powder diffraction (XRD) analysis. The particle sizes were found to be 5-35 nm from Transmission Electron Microscopy (TEM) and Scherer's formula. The hysteresis in the M-H behavior shows the presence of room temperature ferromagnetism in Mn  doped ZnO. XPS results show that there is Mn²⁺ions in all Mn doped samples. Antiferromagnetic interaction between neighboring Mn-Mn ions suppressed the ferromagnetism at higher doping concentrations of Mn.