This article discusses the use of diatom in biosensing and various applications. A thorough understanding of the biosensing properties of diatoms is essential for the advancement of life sciences technologies. This review elucidates the emerging significance of diatoms in biosensing applications by highlighting the high surface area-to-volume ratio, biocompatibility, and facile functionalization of them. We examined the possible application of diatoms as flexible biosensing systems for the detection of various analytes, such as biological molecules, heavy metals, and poisons, by considering the findings of earlier research. Additionally, to show how diatoms can be used to create precise and sensitive biosensors, by integrating with several transduction modalities, including optical, electrochemical, and piezoelectric methods. We also delve into the potential applications of diatom-based biosensing in the future as well as pertinent topics such as repeatability, stability, and scalability. This provides an in-depth analysis of the quickly evolving field of diatom-based biosensing, which could affect several industries, such as environmental monitoring, food security and medical diagnostics.