High Curie-temperature 0.63Bi(Mg_1/2Ti_1/2)O₃–0.37PbTiO₃ (BMT–PT) ferroelectric thin films with a morphotropic phase boundary composition were successfully fabricated on Pt(111)/Ti/SiO₂/Si substrates by sol–gel spin-coating method. The effect of annealing temperatures on the structure and electrical properties of BMT–PT thin films was explored. The scanning electron microscopy and atomic force microscopy images indicate that the film annealed at 675°C for 30 min has a relatively dense and uniform microstructure and a thickness of about 375 nm, together with optimal dielectric and ferroelectric properties of remnant polarization 17.8 μC/cm², coercive field 75 kV/cm, dielectric permittivity 1477, and loss tangent 0.07 at 1 kHz. The results indicate that the BMT–PT thin film has potential applications in high-temperature ferroelectric devices.