The invention discloses a high elasticity fiber blended spinning method and an elastic fabric thereof. The high elasticity fiber is prepared by blending cotton fiber, nylon filament embedded with polyamide fiber, spandex, and worsted fiber, the mass ratio of the four components of cotton fiber, nylon filament embedded with polyamide fiber, spandex, and worsted fiber is 3: 1: 2: 1. The elastic fabric comprises a bottom layer, an interlayer and a face layer, the three layers of materials are fixed by stitching, a lining fabric layer is arranged on the back of the bottom layer, and the fabric layer comprises warp and weft; the interlayer is provided with an elastic layer and a thermal storage layer; high elasticity fiber is arranged in the elastic layer. According to the high elasticity fiberblended spinning method, composite effects and functional complementarities are produced by utilizing four different fiber combinations for the first time, moisture absorption and wear comfort of thefabric are improved, on the basis of ensuring wear resistance and dimensional stability of the fabric, the elasticity of the fabric is improved, and the properties of anti-bacteria, bacteriostasis, anti-ultraviolet, moisture absorption, deodorization and perspiration are added.