A biopolymer-based bicontinuous hydrogel system was developed to guide rapid 3D cell migration. This hydrogel consists of a covalently crosslinked gelatin network and a physical hyaluronic acid network with guest-host interactions. Bicontinuous hydrogels form through controlled solution immiscibility, creating continuous subdomains and high micro-interfacial surface areas that enable rapid 3D migration. The hydrogel's microstructures provide pathways for cell migration, influenced by biochemical and biophysical signals. The study shows that bicontinuous hydrogels support rapid cell migration across various cell types and physiologically relevant contexts, such as cell spheroids, ex vivo tissues, and in vivo tissues. The hydrogel's bicontinuous structure, formed by controlled immiscibility, allows for distinct gelatin-rich (GR) and gelatin-poor (GP) domains, which influence cell migration. The GR domains are stiffer and more connected, while the GP domains are softer and less connected. The high interfacial surface area and connectivity of the bicontinuous structure enable cells to migrate along microinterfaces. The study also demonstrates that the bicontinuous hydrogel supports cell migration in both in vitro and in vivo environments, with cells migrating along microinterfaces in ex vivo and in vivo tissue repair scenarios. The findings suggest that bicontinuous hydrogels can be used to guide cell migration for tissue repair applications.A biopolymer-based bicontinuous hydrogel system was developed to guide rapid 3D cell migration. This hydrogel consists of a covalently crosslinked gelatin network and a physical hyaluronic acid network with guest-host interactions. Bicontinuous hydrogels form through controlled solution immiscibility, creating continuous subdomains and high micro-interfacial surface areas that enable rapid 3D migration. The hydrogel's microstructures provide pathways for cell migration, influenced by biochemical and biophysical signals. The study shows that bicontinuous hydrogels support rapid cell migration across various cell types and physiologically relevant contexts, such as cell spheroids, ex vivo tissues, and in vivo tissues. The hydrogel's bicontinuous structure, formed by controlled immiscibility, allows for distinct gelatin-rich (GR) and gelatin-poor (GP) domains, which influence cell migration. The GR domains are stiffer and more connected, while the GP domains are softer and less connected. The high interfacial surface area and connectivity of the bicontinuous structure enable cells to migrate along microinterfaces. The study also demonstrates that the bicontinuous hydrogel supports cell migration in both in vitro and in vivo environments, with cells migrating along microinterfaces in ex vivo and in vivo tissue repair scenarios. The findings suggest that bicontinuous hydrogels can be used to guide cell migration for tissue repair applications.