Abstract: The disclosure provides marine polysaccharide vector-based anthocyanin nanoparticles, using marine polysaccharides, food-borne fluorescent nanoparticles and sodium hyaluronate as a composite vector to be combined with anthocyanin, and is prepared by a method: S1, dissolving sodium alginate in phosphate buffered saline, and successively adding EDC, HOBt and the food-borne fluorescent nanoparticles to obtain a fluorescence-alginate complex; S2, adding the fluorescence-alginate complex into a mixture of DMF and DCM, and then adding DIC and DMAP; S3, adding the anthocyanin and hyaluronic acid, and then removing a solvent; and S4, removing unreacted small molecules, and carrying out freeze drying. The disclosure can improve the anthocyanin stability, control the slow release of the anthocyanin, has the characteristics of fluorescent tracing, can be used as a fluorescent marker for in vivo imaging of animal tissues, organs, etc.