Biological heart valves (BHVs) are an important alternative to mechanical valves for patients requiring heart valve replacement. Despite their advantages in terms of biocompatibility and reduced need for anticoagulation, challenges remain in ensuring the long-term durability and optimal function of these valves. Animal models have played a pivotal role in understanding BHV performance and providing insights into their structural integrity, durability, and interaction with host tissues. This article provides a comprehensive review of biological heart valve performance, focusing on the contribution of animal studies to the understanding of valve degeneration, calcification, and hemodynamic function.