BiScO3–PbTiO3 thin film was hydrothermally deposited on Nb-doped SrTiO3  single crystal substrate at 180 °C with a large thickness of 3.1 μm. The x-ray diffraction and high resolution transmission electron microscopy confirmed the epitaxial growth relationship between the BSPT thin film and Nb-STO substrate. Single-crystal-like polarization hysteresis loops were observed, with the remanent polarization of 30 μC/cm2. Piezoelectric force microscopy revealed a single +c domain structure of the film, while exceptional linear piezoelectric response was observed with the effective piezoelectric constant d33* of 65 pm/V. The temperature dependence of the effective d33* indicated that this film exhibited a high temperature stability.