The invention relates to a light, thin and cool wool fabric preparation method, which includes twisting vinylon and wool yarns in parallel, and air jet vortex spinning; respectively performing hydrophilic finishing and water repellent finishing on polyester filaments; taking the outer layer as wool yarns, and the inner layer as polyester low elastic yarn structure woven fabrics; and after weaving,open-width baking, adopting a low-temperature non-alkali oxygen process to remove vinylon fibers, dyeing wools, soft finishing and post-finishing. The light, thin and cool wool fabric obtained by themethod has good moisture absorption and quick drying performance.