Nanoparticles of undoped and La doped CdO have been obtained by simple precipitation method with different La concentrations (3, 5, 10 and 15 at. %). Influence of La dopant on crystal structure, microstructure, optical properties and antibacterial efficiency of the nanoparticles was investigated by means of X-ray diffractometer, field emission scanning electron microscope, photoluminescence spectrometer and antibacterial examination. Crystal structure analysis reveals that La doping appreciably increases the crystalline size and also it shows the polycrystalline nature of the samples. Microstructural investigation shows that the samples contain nanoparticles. The optical property has determined by the PL spectral analysis. It has also been found that La dopant with CdO increases the zone of inhibition for both gram positive and gram negative bacterial strains.