An embodiment can provide a method for producing a polyamide-imide film which is colorless and transparent and has excellent mechanical properties, the method comprising: a step of producing a polyamide-imide polymer solution by polymerizing an aromatic diamine compound, an aromatic dianhydride compound, and a dicarbonyl compound; a step of producing a gel sheet by extruding, casting and drying the polymer solution; and a step of producing a polyamide-imide film by heat-treating the gel sheet, wherein the viscosity of the polymer solution is 100,000 to 500,000 cps, and the polyamide-imide film has a yellowness index of 5 or lower, a haze of 2% or lower, a transmittance of 85% or above and a modulus of 5.0 GPa or above, at a thickness of 20 μm to 75 μm.