The invention discloses a preparation method of an asparagus drink with a function of reducing intima-media thickness, and belongs to the field of food. The method includes the following steps: performing washing on asparagus materials, and then performing breaking, extracting, centrifuging, filtering through membrane and decoloring; performing electrodialysis treatment, wherein the conductivity of the electrodialysis is controlled within 1000-4000 us/cm, the mass concentration of feeding liquid is 5%-25%, liquid-feeding time is 1-8 h and liquid-feeding temperature is 25 DEG C to 60 DEG C; concentrating the liquid after the electrodialysis treatment to obtain asparagus juice; and adding gamma-aminobutyric acid and theanine into the asparagus juice so as to obtain the asparagus drink. The invention also discloses the asparagus drink prepared through the method and the applications of the asparagus drink. The method provided by the invention is easy to operate and the asparagus drink prepared through the method has very little impurity content and is applied to medicines, food or health care products having the function of reducing the intima-media thickness so that the intima-media thickness can be reduced.