(Pb, La)(Zr, Ti)O3 antiferroelectric thick films with (100)-preferred orientation were fabricated on Pt(111)/Ti/SiO2/Si(100) substrates via a sol–gel method. The electric-field-induced antiferroelectric (AFE) to ferroelectric (FE) phase transition characteristics were studied by C (capacitance)–E (electric field) measurements at different temperature. The films were in AFE state under 0 kV/cm below 122 °C, and the switching field values decreased, with increasing temperature. The films were in FE state between 122 and 135 °C, and when the temperature above 135 °C, the films were in PE state. The temperature-dependent dielectric parameters were deconvoluted using a Gaussian fit multi-peaks showed that two typical phase transitions were discovered. The first peak is the AFE-to-FE phase transition and the second peak is the FE-to-PE phase transition which has been verified by C–E tests.