ZnMn codoped BaTiO3 films were fabricated on Si (100) and LNO/Si (100) substrates by a solgel procedure. In order to study the effects of different doping levels on the microstructure and ferroelectric phase of BaTiO3 thin films, BTO films doped with Zn and Mn, respectively, were also investigated. Both the characterization of Xray diffraction (XRD) and atomic force microscope (AFM) indicate uniform and dense films with average grain size under 30 nm. By comparisons of the optical constant refractive index and extinction coefficient of BaTiO3 films in the wavelength from 400 nm to 700 nm, it was obtained that there is a change in the optical band gap due to the different amount of Zn and Mn added. Furthermore, a better defined PE loop with a remnant polarization of 11.26 μC/cm2 shows that Zn and Mn dopanting play an essential role in ferroelectric improvement.