Abstract: The technical field of active substance preparations is belonged to, and provided are astaxanthin pickering emulsion with colon targeted delivery function, and a preparation method and application method thereof. The preparation method includes the following steps: S1, reparation of deacetylated-oxidized chitin nanofiber (DE-TO-ChNF)/carboxymethyl konjac glucomannan (CMKGM) nanogel; S2, preparation of astaxanthin oil phase; and S3, preparation astaxanthin pickering emulsion. Natural polysaccharide derivatives DE-TO-ChNF and CMKGM are used as raw materials, and stable crosslinking between covalent bonds and non-covalent bonds are formed between molecules in a composite system through the NHS/EDC, so as to form a stable nanogel. Then the nanogel is used as emulsifier and flaxseed oil rich in astaxanthin is used as oil phase to prepare the astaxanthin pickering emulsion by homogenization.