Due to the exceptional optical properties such as biocompatibility, and low toxicity, carbon nanodots(CNDs) have emerged as a potential material for biosensing, drug delivery, and bioimaging. As a result,CNDs preparation, properties, and applications have sparked much attention. Its advantages include greatbiocompatibility in vitro and in vivo, photobleaching resistance, ease of surface functionalization and bioconjugation,excellent colloidal stability, environmentally safe manufacturing, and low cost. This allowedCNDs to replace traditional fluorescent heavy metal-containing semiconductor quantum dots or organicdyes. CNDs have demonstrated a wide range of applications, despite the fact that the mechanism of theirphotoluminescence remains a mystery. In this review, we examine current advancements in the field ofCNDs and provide a complete overview of their synthesis techniques and emission processes along withtheir applications in biosensing, drug delivery, bioimaging, wound healing, and disease detectionbiosensors.