Decellularized extracellular matrix (dECM)–based biomaterials are of great clinical utility in soft tissue repair applications due to their regenerative properties. Multi-layered dECM devices have been developed for clinical indications where additional thickness and biomechanical performance are required. However, traditional approaches to the fabrication of multi-layered dECM devices introduce additional laminating materials or chemical modifications of the dECM that may impair the biological functionality of the material. Using an established dECM biomaterial, ovine forestomach matrix, a novel method for the fabrication of multi-layered dECM constructs has been developed, where layers are bonded via a physical interlocking process without the need for additional bonding materials or detrimental chemical modification of the dECM. The versatility of the interlocking process has been demonstrated by incorporating a layer of hyaluronic acid to create a composite material with additional biological functionality. Interlocked composite devices including hyaluronic acid showed improved in vitro bioactivity and moisture retention properties.