Biosensors are emerging diagnostic devices that combine biology and technology to detect and quantify target analytes, allowing for very sensitive, noninvasive, and real-time monitoring of biochemical and physical properties. When coupled with scaffolds, bioreactors, or microfluidic chips, biosensors provide dynamic control over cell viability and differentiation, extracellular matrix deposition, inflammatory responses, and overall structural maturation. Measuring these parameters in situ, in a tissue-engineered construct, is essential for improving tissue regeneration and personalized treatments. Recent advancements in miniaturization, biomaterials, artificial intelligence, and wireless communication have further enhanced the utility of biosensors in tissue engineering applications. This chapter aims to provide an overview of biosensors in the context of osteochondral tissue engineering. It discusses the fundamental principles of biosensors and their classification based on sensing mechanisms, highlighting their potential in monitoring cell environment and behavior. In addition, it provides key applications of integration of biosensors with tissue-engineered platforms and discusses challenges, limitations, future directions, and opportunities in the field.