BaTi5O11 thin films with single-layer thicknesses about 400 nm were deposited on the Si substrates by sol-gel method. The influence of surface morphology, optical and dielectric properties was mainly investigated. The diffraction pattern showed that the annealed films exhibited a polycrystalline microstructure, and the increase in grain size of BaTi5O11 thin films occurred with an increase in annealing temperature and the pH value. In addition, it was also showed that the porosity was increased with a higher preheating temperature and annealing temperature. These results indicate that the suitable processing parameters are beneficial to improve the microstructure, optical, dielectric and electrical performances of BaTi5O11 thin film.