Ribose is an essential sugar for present life as a building block of RNA, which could have both stored information and catalyzed reactions in primitive life on Earth. Meteorites contain a number of organic compounds including components of proteins and nucleic acids. Among the constituent molecular classes of proteins and nucleic acids (i.e., amino acids, nucleobases, phosphate, and ribose/deoxyribose), the presence of ribose and deoxyribose in space remains unclear. Here we provide evidence of extraterrestrial ribose and other bioessential sugars in primitive meteorites. Meteorites were carriers of prebiotic organic molecules to the early Earth; thus, the detection of extraterrestrial sugars in meteorites implies the possibility that extraterrestrial sugars may have contributed to forming functional biopolymers like RNA.