In this study for the first time, poly(vinyl alcohol) (PVA)-ABO3 (BaCeO3/SrCeO3/SrZrO3) nanocomposite membranes were prepared as proton exchange membrane for high-temperature proton exchange membranes fuel cell (HT-PEMFC). Proton ion-conducting material based on perovskite ceramic ABO3 were prepared by sol-gel combustion method. PVA-ceramic nanocomposite membrane containing BaCeO3, SrCeO3, SrZrO3, nanoparticles in various compositions were developed by solutions casting method. Structural features are confirmed by X-ray diffraction (XRD) and FTIR. Uniform dispersion of ceramic particles in polymer membrane is confirmed by scanning electron microscopy. Proton-conducting ability of the composite membranes was revealed by impedance spectroscopy. The ion-conducting ability of the membrane was studied under three conditions (1) by hydrating the membrane, (2) by phosphoric acid doping, and (3) by sulphuric acid doping. Proton conductivity of phosphoric acid doped nanocomposite membrane is found to be highest amongst the others. The dynamics of proton ion conduction were revealed by electric modulus spectrum. The composite membrane exhibited good mechanical strength and thermal stability up to 120 °C. The PVA-BaCeO3 (PVA-BCO) composite membrane demonstrates maximum proton ion conductivity 2.84 × 10−3 S/cm as compared to PVA and other PVA-based composites at 120 °C using phosphoric acid doping. For PEMFC applications, phosphoric acid-doped composite membranes made of PVA and barium cerate (BaCeO3) have a high potential of effectiveness.