The process for preparing a thermally shrinkable multilayer film composed of a polyamide resin layer as one surface layer and a sealant material layer as the other surface layer includes the step of causing the polyamide resin layer of the oriented laminate film to absorb water in the amount of 7.0% by weight or more before or during the thermal treatment. The laminate film is then dried so as to cause the polyamide resin layer to make the water content in the range form 2.5% by weight to 6.5% by weight while maintaining the oriented laminate film at temperatures of 90.degree. C. or lower after or during the thermal treatment. The thermally shrinkable multilayer film thus prepared is suitable for thermally shrinking packing foods such as roast meat or fresh cut meat.