The invention discloses lactobacillus rhamnosus, cultivation of the lactobacillus rhamnosus and a microcapsule method. The bacterial strain is preserved in China General Microbiological Culture Collection Center (CGMCC); a registering number is CGMCC NO.3994; a Latin name of the bacterial strain is Lactobacillus rhamnosus LC-STH-13; morphological characteristics are gram-positive bacteria, short-rod bacterial thallus, no motion, no gemma, circular bacterial colony, milk white, tidy edges, smooth surfaces and protuberant cores. The invention further discloses a 16S ribosome DNA (Deoxyribose Nucleic Acid) (16S rDNA) complete sequence of the lactobacillus rhamnosus. The lactobacillus rhamnosus has the advantages that a culture is short in growth cycle, high in breeding speed and- produced lactic acid concentration. The lactobacillus rhamnosus can -colonize and survive in an intestinal tract, improves a mucosal barrier function of a gastrointestinal tract, has a function of improving the gastrointestinal tract, and restrains the colonization of harmful bacteria; and after being embedded by a microcapsule, the lactobacillus rhamnosus has stronger ability to resist the poor environment.