Glycosphingolipids are widely present in cell membranes and serum. They either exist in free form or are complexed with other proteins. The glycan head group determines the biological function of glycosphingolipids. Abnormal glycosylation of glycosphingolipids is closely related to various cancers, such as breast cancer, lung cancer, and brain tumors. Glycosphingolipid glycans are also involved in many cellular processes, such as signal transduction, receptor function, and cell differentiation.