Barium calcium titanium Ba1−xCaxTiO3 (BCTx) is an important ferroelectric and antiferroelectric material. The BCTx (x = 0, 0.1, 0.21, 0.3) thin films were prepared on (100)-oriented LaNiO3/Si substrates by a sol–gel process. X-ray diffraction showed that all the BCTx thin films exhibited a single perovskite phase with (100)-preferred orientation. The temperature dependent dielectric properties showed that the BCT0.21 film which is near the solubility limit of CaTiO3 (CT) in BaTiO3 (BT) had a large dielectric constant and the lowest temperature coefficient. Although the dielectric loss for BCT0.21 film is slightly higher than the others, the BCT0.21 thin film is still a promising candidate for the devices which demand high and stable memory capability in temperature changeable environment.