Abstract A new in situ process for depositing MgB₂ film is being developed in the present study as a candidate method to facilitate the mass production of MgB₂-thin-film superconducting tapes. Here, a MgB₂ film was synthesized on a heated copper substrate via “hybrid deposition,” comprising thermal evaporation of magnesium and sputtering of boron. High-temperature post-annealing was performed to increase the critical current density (J _c ) of the MgB₂ thin films obtained via hybrid deposition. The J _c of the MgB₂ film deposited at 360 °C by hybrid deposition and post-annealed at 430 °C was drastically improved to 1100 A mm⁻² at 20 K under 4 T, 79 000 A mm⁻² at 15 K under 3 T, and 59 000 A mm⁻² at 10 K under 5 T under a magnetic field parallel to the film. It was expected that the incorporation of hybrid deposition in processing using a reel-to-reel machine would facilitate the synthesis of high-J _c , long MgB₂-thin-film superconducting wires.