The invention discloses semi-worsted emerald pearl fiber blended health care yarn and a production method and application thereof. The weight percent of an emerald pearl fiber in the blended yarn is 20-40%, the weight percent of a flax fiber in the blended yarn is 15-30%, the weight percent of a wool fiber in the blended yarn is 30-50%, and the weight percent of a cashmere fiber in the blended yarn is 10-35%. According to performance indexes of the blended yarn, the single yarn breaking strength is 11.4-20.3cN/tex, the single yarn breaking strength variation coefficient Cv value is 10.3-17.9%, and the yarn evenness variation coefficient Cv value is 13.6-20.8%. Not only do the semi-worsted blended health care yarn made of the emerald pearl fiber, the flax fiber, the wool fiber and the cashmere fiber and a manufactured fabric have healthcare functions of antibacterium, deodorization, inflammation diminishing, odor removal, skin care, fitness, beauty and skin moistening and the like, but also the fabric is good in skin friendliness, comfort, moisture absorption, air permeability and dyeing property, soft in touch, attractive and elegant in product appearance, bright in color, full of gloss, good in ultraviolet resistance, unique in appearance and wide in product purpose, and high-quality healthcare fabrics can be produced in the fields of knitting or weaving.