The invention relates to a preparation method of a high-sun-resistance high-perspiration-fastness polyamide case material. The preparation method comprises the following steps: preparing a dyeing liquid through adding 0.5-4.5%owf of a dye, 0.25-0.75%owf of a leveling agent and 1-3%owf of a light fastness reinforcing agent; adjusting the pH value to 3.5-5.5, and allowing the bath ratio to be 1:10-20; and heating to 40-50DEG C, adding a polyamide case cloth sample, stirring for dyeing for 5-10min, heating to 100DEG C, carrying out stirring heat-insulation dyeing for 30-45min, cooling to room temperature, soaping, washing with water, and drying. The case material prepared in the invention has a high sun resistance and a high perspiration fastness; and the preparation method has the advantages of simple operation, no need of the addition of a device, and controllable cost.