Heat exchangers are central to modern thermal systems, including power plants, refrigeration units, automotive engines, and renewable energy technologies. However, conventional designs face inherent limitations in achieving maximum thermal efficiency due to material conductivity constraints, fouling, size restrictions, and parasitic energy losses. Recent advancements in metamaterialsengineered structures with tailored thermal, electromagnetic, and acoustic properties have opened new possibilities for overcoming these challenges. Metamaterial-enhanced heat exchangers leverage structured surfaces, phononic bandgaps, and anisotropic conduction pathways to significantly improve heat transfer rates while minimizing pressure drop. This paper explores the principles, designs, and emerging applications of metamaterial-based heat exchangers, particularly in ultra-efficient thermal systems for aerospace, energy, and industrial applications. It also discusses fabrication challenges, integration issues, and future research directions that may revolutionize thermal management technologies