The invention relates to a traditional Chinese medicine for oral administration, which cures post-herpetic neuralgia, and the preparation method thereof. The formula of the traditional Chinese medicine comprises the following components by percentage: 16% of alcohol processed radix paeoniae alba, 8% of liquorice, 6% of rhizoma atractylodis macrocephalae, 12% of isatis root, 12% of glabrous greenbrier rhizome, 6% of alcohol processed radix angelica sinensis, 6% of salvia miltiorrhiza, 6% of processed frankincense, 6% of processed myrrh, 7% of scorpio, 5% of centipede, 6% of mud eel blood and 4% of towel gourd vegetable sponge. The preparation method comprises the following steps: preparing alcohol processed radix paeoniae alba, alcohol processed radix angelica sinensis, processed frankincense and processed myrrh by adopting the traditional method; pulverizing scorpio, centipede, mud eel blood, processed frankincense and processed myrrh together and sieving with a 120-mesh sieve for later use; watering and decocting alcohol processed radix paeoniae alba, liquorice, rhizoma atractylodis macrocephalae, isatis root, glabrous greenbrier rhizome, alcohol processed radix angelica sinensis, salvia miltiorrhiza and towel gourd vegetable sponge respectively for two times and one hour per each time, and pulverizing into fine powder; and split-charging in capsules. The preparation method has the effects of nourishing Yin, tonifying Qi, freeing channel and relieving pain, and has the advantages of no side effect, significant curative effect, and great popularization and application values.