In this study, CdO (Cadmium Oxide) nanoparticles with different derivation techniques were prepared using the microwave-assisted method. The reactants used were Cadmium Acetyl Acetonante Cd(acac), NaOH (Sodium Hydroxide), and Na2CO3(Sodium Carbonate). The prepared samples were characterized using X-ray diffractions, UV-Vis diffuse reflectance spectroscopy, thermogravimetric analysis and differential thermal analysis, photoluminescence (PL), and Fourier transform infrared spectroscopy. All CdO nanoparticles have cubic structures with different optical characteristics. The band gap energy of CdO derived from direct calcination Cd(acac) was around 1.5 eV; the energy of CdO derived from Na2CO3 was around 3.8 eV; and the CdO synthesized using NaOH had a band gap around 2.1 eV. The strong emission at 395 nm (violet) from PL measurement corresponded to the band-edge emission of CdO. This photocatalytic activity result indicated that the CdO nanoparticles derived from calcination Cd(acac) to CdO nanoparticles exhibited high photocatalytic activity with a percentage degradation of approximately 77 %.