The invention discloses a medicinal composition for treating primary hypertension, and a preparation method and an application thereof, and belongs to the technical field of traditional Chinese medicines. The effective components of the medicinal composition comprise, by weight, 20-25 parts of Radix Astragali, 10-15 parts of vegetable sponge of luffa, 2-4 parts of charred human hair, 15-20 parts of Salvia miltiorrhiza, 15-20 parts of Achyranthes bidentata, 5-8 parts of Chinese magnoliavine, 10-15 parts of panax notoginseng, 10-15 parts of radix paeoniae rubra, 5-8 parts of chicken's gizzard membrane, 15-20 parts of Rhizoma Atractylodis Macrocephalae, 15-20 parts of Chinese yam, 15-20 parts of Poria cocos, 6-10 parts of peach seeds, 14-18 parts of Polygonum multiflorum and 10-15 parts of Chinese angelica root. The medicinal composition prepared through reasonable compatibility of traditional Chinese medicines can improve the functions of all internal organs and promote qi-blood moving to realize yin and yang balance in bodies, genuine qi and healthy energy strengthening and difficult assemblage of phlegm turbidity, so blood stasis transformation, phlegm elimination and blockage stasis elimination effects are reached.