N-doped titanium dioxide (TiO₂) thin films are grown on Si(100) and indium tin oxide (ITO)-coated borosilicate glass substrates by metal-organic (MO)CVD. The intrinsic doping of TiO₂ thin films is achieved using all-nitrogen-coordinated Ti precursors in the presence of oxygen. The titanium amide-guanidinate complex, [Ti(NMe₂)₃(guan)] (guan = N,N′-diisopropyl-2-dimethylamidoguanidinato) has been developed to compensate for the thermal instability of the parent alkylamide [Ti(NMe ₂)₄]. Both of these amide-based compounds are tested and compared as precursors for intrinsically N-doped TiO₂ at various deposition temperatures in the absence of additional N sources. The structure and morphology of TiO₂ thin films are characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). Rutherford back scattering (RBS), nuclear reaction analysis (NRA), and secondary ion mass spectrometry (SIMS) analyses are performed to determine N content and distribution in the films. The optical and photoelectrochemical properties of TiO₂ thin films on ITO substrates are also examined. N-doped TiO₂ thin films, grown from [Ti(NMe ₂)₃(guan)] at 600 °C, exhibit the lowest optical absorption edge (3.0 eV) and the highest visible light photocurrent response. When compared to undoped TiO₂, while in UV light photoconversion efficiency decreases significantly, the intrinsically N-doped TiO₂ shows enhanced photocurrents under visible light irradiation. The intrinsic doping of TiO₂ thin films with nitrogen by MOCVD and the investigation of the photo-electrochemical properties of the films are reported. N-doped anatase phase TiO₂ thin films are grown on Si(100) and ITO substrates under specific processing conditions, using [Ti(NMe₂) ₄] (1) and [Ti(NMe₂)₃(guan)] (2) (guan = N,N′-diisopropyl-2-dimethylamidoguanidinato) as precursors. The films grown from [Ti(NMe₂)₃(guan)] at 600 °C show relatively large surface roughness and lower bandgap related with high N content.