Abstract: Lasso peptides, natural products found in bacteria, are bioactive peptides belonging to a peculiar family of ribosomally synthesized and post-translationally modified peptides with an unusual lasso structure, an array of anti-bacterial or anti-fungal activity, and anti-viral or anti-tumor functions, with no or low immunogenicity. Lasso peptides can be classified into four types according to the numbers and positions of the disulfide bonds. Due to their particular threaded structure, lasso peptide presents remarkable thermal and proteolytic stability compared with linear peptide. Lasso peptide has been widely applied in the manufacturing of medicines and foods, and is expected to be used as delivery carrier of biologics, which has become a hot spot for the design of polypeptide drugs.