The invention provides a health-care spandex fiber which is formed by combining a wrapper and a core part, wherein the section of the fiber is solid; the mass percentage of the core part accounts for 30-70% of that of the fiber and the mass percentage of the wrapper accounts for 30-70% of that of the fiber; and a preparation method of the health-care spandex fiber comprises the following steps of: 1, preparing a health-care spandex core part by utilizing a melt spinning technology according to a formula proportion; 2, preparing a health-care spandex fiber wrapper by utilizing a dry-method spinning technology according to the proportion; and 3, spinning by utilizing a special spinneret plate combined piece through a conventional dry-method spinning equipment process so as to obtain a health-care spandex. The health-care spandex disclosed by the invention has the effects of eliminating the peculiar smell, absorbing the moisture and proofing moulds, and inhibiting bacteria and expelling parasites; the health-care spandex can be contacted with a human body to remove the humidity and absorb the sweat so as to accelerate the blood circulation and the metabolism of the human body and relieve fatigues; and the health-care spandex also has the aroma of plant essences, and furthermore is good in utilization performance and can meet the requirements on homespun in processes of spinning, weaving, dyeing and finishing.