Significance Fiber materials have great impact on our daily lives, with their use ranging from textiles to functional reinforcements in composites. Although the manufacturing process of manmade fibers is potentially limited by extensive energy consumption, spiders can readily spin silk fibers at room temperature. Here, we report a class of material that is based on a self-assembled hydrogel constructed with dynamic host–guest cross-links between functional polymers. Supramolecular fibers can be drawn from this hydrogel at room temperature. The supramolecular fiber exhibits better tensile and damping properties than conventional regenerated fibers, such as viscose, artificial silks, and hair. Our approach offers a sustainable alternative to current fiber manufacturing strategies.