The invention discloses a baokangling multi-element probiotics oral liquid for treating a digestive system disease and a preparation method of the oral liquid, wherein the oral liquid is comprised of Radix Codonopsis, Atractylodes Rhizoma, Astragalus mongholicus, Rhizoma Dioscoreae, Crataegus pinnatifida, Fructus Hordei Germinatus, Radix Glycyrrhizae, Poria cocos, Ganoderma lucidum, pericarpium citri reticulatae, Fructus citrus sarcodactylis, Fructus Amomi, Cortex Magnoliae Officinalis, Lignum Aquilariae Resinatrm, Cyperus rotundus, Fructus Lycii, Angelica sinensis, Radix Salviae Miltiorrhizae, bletilla striata, unshelled Ascidia, Radix Bupleuri, Radix Paeoniae alba, Corydalis yanhusuo, Radix Glehniae, Polygonatum odoratum, Fructus Schizandrae, Rhizoma Coptidis, peeled Semen Raphani, Semen Lablab Album, Panax notoginseng powder, Fructus Aurantii Immaturus, Radix Aucklandiae, Coix seed, endothelium corneum gigeriae galli, Fructus Corni, lotus seeds and Lindera aggregate. The above traditional Chinese medicinal materials are decocted according to a certain weight ratio and subjected to probiotics fermentation so as to obtain the multi-element probiotics oral liquid. The oral liquid has unique treating effect proven by clinical application. The traditional Chinese medicines are decomposed from macromolecules to micromolecules through biotransformation, so that the effects of absorbing quickly and taking effect instantly are obtained; furthermore, the secondary components and invalid components of the traditional Chinese medicines are converted into the essential nutrient substances incapable of synthetizing by themselves in the human body, so that the curative effect is improved. The application range of the oral liquid is broadened and the quality guarantee period is prolonged.