TiO₂ is widely used as a ceramic material field which has been used in many research fields due to its low cost, high photocatalytic activity, effective charge separation and high oxidation-reduction performance. In this study, we synthesized of TiO₂ nanoparticles by Nitrogen doped to decrease of band-gap energy which improve the photocatalytic activity on the visible light region. Titanium tetraisopropoxide, isopropyl alcohol, acetyl acetone, and acetic acid were prepared to TiO₂ precursor solution. TiO₂ nanoparticle was titration of pH by ethylene diamine in nitrogen gas condition. To explore the visible light photocatalytic activity of the nitrogen doped TiO₂ photocatalyst in variety conditions of aging time, heat temperature and the removal of methylene blue dye was investigated. The synthesized TiO₂ nanoparticles crystalline structure and morphology were characterized by XRD, SEM and TEM.