Biomimetic designs based on micro/nanoscale manipulation and scalable fabrication are expected to develop new-style strong,tough structural materials.Although the mimicking of nacre-like ’brick-and-mortar’structure is well studied,many highly ordered natural architectures comprising 1D micro/nanoscale building blocks still dude imitation owing to the scarcity of efficient manipulation techniques for micro/nanostructural control in practical bulk counterparts.Herein,inspired by natural twisted plywood structures with fascinating damage tolerance,biomimetic bulk materials that closely resemble natural hierarchical structures and toughening mechanisms are successfully fabricated through a programmed and scalable bottom-up assembly strategy.By accurately engineering the arrangement of 1D mineral micro/nanofibers in biopolymer matrix on the multiscale,the resultant composites display optimal mechanical performance,superior to many natural,biomimetic and engineering materials.The design strategy allows for precise micro/nanostructural control at the macroscopic 3D level and can be easily extended to other materials systems,opening up an avenue for many more micro/nanofiber-based biomimetic designs.