Quantum catalysis offers a new perspective on how biological systems achieve remarkable efficiency and selectivity in biochemical reactions. Traditional catalysis models based on classical physics often fall short in explaining the extraordinary rates observed in enzyme-catalyzed processes, where turnover frequencies can exceed 103–104 s−1 under mild conditions. This chapter explores how fundamental quantum phenomena such as tunneling, zero-point energy stabilization, and coherence play crucial roles in enhancing catalytic performance in biological systems. Enzymes involved in key metabolic pathways accelerate proton, electron, and hydride transfers by leveraging quantum tunneling, evidenced by kinetic isotope effects ranging from 20 to 50, well beyond classical limits (~7). Structural fluctuations of approximately 0.3 Å in enzyme active sites modulate tunneling efficiencies, resulting in catalytic rate enhancements up to 200%. Additionally, transient quantum coherence lasting between 100 and 500 femtoseconds has been identified as a mechanism that improves charge transfer efficiency in photosynthesis and respiration. Despite these promising insights, challenges remain in fully understanding and replicating these quantum effects in synthetic systems due to the fragile nature of quantum states and complex protein dynamics. Recent advances in ultrafast spectroscopy, cryo-electron microscopy, and quantum computational modeling are beginning to unravel these behaviors and offer routes for engineering improved biocatalysts. This chapter provides an overview of the fundamental concepts of quantum catalysis in biochemical reactions, summarizes key experimental findings with quantitative insights, and discusses current challenges and future opportunities.