Amyloid is a fibrous structure comprising stacked peptides and proteins, and specifically adopts a cross-β-sheet structure in which β-sheets are aligned perpendicular to the fiber axis. The accumulation of amyloids in vivo generally causes various diseases, including systemic amyloidosis and Alzheimer disease, 2 although non-pathogenic pre-melanosomal protein amyloid present in melanosomes is also reported. On the other hand, recent works have unveiled functional amyloids formed from short peptides that are able to catalyze chemical reactions (so-called "catalytic amyloids"). The catalytic activities of the amyloids depend on inherently highly reactive moieties such as metal salts and nucleophilic functionalities. Catalytic amyloids indiscriminately react with a wide range of substrates possessing the reaction sites, however, and selective conversions of the substrates with equivalently reactive moieties remain challenging. In addition, the scope of the reactions using catalytic amyloids is currently limited mostly to ester hydrolysis, aldol/retro-aldol reactions, and aromatic ring oxidations. In the present study, we devised a new catalysis system, i.e., catalysis driven by amyloid-substrate complex (CASL, Fig. ), to extend the substrate selectivity and reaction scope of catalytic amyloids.