Abstract: With CaCO3 and TiO2 as raw materials, they were separately baked at 1100, 1200, 1300, 1400 and 1500°C, and then characterized by XRD, SEM, FT-IR, UV-vis. The results showed that the high-purity CaTiO3 can be synthesized above 1400°C. With the temperature increasing, the micro morphology of synthesized CaTiO3 surface changes from irregularly polygonal to smooth, and the agglomeration of particles tends to be apparent. The different contents of CaTiO3 and TiO2 lead the absorbance of catalyst to be greatly different in UV-visible region. As the experimental results of photocatalytic performance evaluation, the degradation rate and efficiency of methylene blue both decrease with temperature increasing, and the reaction rate constant decreases by 50%. The degradation of the methylene blue with calcium titanate is comparatively in line with the characteristics of first-order reaction kinetics.