The influences of CaZrO3 on the dielectric properties and microstructures of BaTiO3 (BT)-based ceramics have been investigated. The experiment results showed that the dielectric constant at room temperature increased with the addition of CaZrO3 in the range of 0–3.0 mol%, which could be explained by the growth of BT grains. XRD analysis revealed that the tetragonality declined as CaZrO3 concentration increased. XRD patterns of BT ceramics with different amounts of CaZrO3 doping were analyzed by a recently developed procedure-materials analysis using diffraction (MAUD), which was based on the Rietveld method combined with Fourier analysis. The results depicted that the high temperature peak of temperature-capacitance characteristics (TCC) was largely dependent on the micro-strain of samples. Furthermore, more CaZrO3 doping resulted in lower porosity and higher density. It was revealed that proper usage of CaZrO3 could improve the dielectric properties significantly, which was benefit to develop X8R multi-layer ceramic capacitors.