Designing biological substitutes capable of restoring, maintaining, or improving tissue function has become a critical objective in modern biomedical research. Tissue engineering serves as the convergence point for material science, molecular biology, and clinical application. With scaffolds playing a pivotal role, the selection of biodegradable polymers and bioactive hydrogels directly influences tissue compatibility and integration. In recent years, decellularized matrices and 3D bioprinting have expanded the possibilities for constructing vascularized and functional tissues. Strategies now focus on mimicking native extracellular matrices and leveraging stem cell-derived organoids to replicate physiological complexity. Whether repairing bone defects or developing liver patches, breakthroughs in tissue engineering are paving the way for next-generation therapeutics and personalized medicine solutions that align with patient-specific needs.