The optical biomedical sensor industry has grown enormously over the past few years and is expected to grow more in the forthcoming days because of the extensive need for point-of-care testing devices. Researchers all over the world are working on the implementation of highly sensitive, reliable, portable, and inexpensive biomedical appliances, which can revolutionize this market. Optical biosensing is a vast topic, and numerous optical sensing techniques have been presented over the years.These techniques and corresponding technological platforms enabling the manufacturing of optical biomedical sensors of different types.the most representative cases are integrated optical biosensors, vertical grating couplers, plasmonic sensors, surface plasmon resonance optical fiber biosensors, and metasurface biosensors, Photonic crystal-based biosensors, thin metal films biosensors, and fiber Bragg grating biosensors，these optical biomedical sensors might enable the identification of symptoms of deadly illnesses in their early stages; thus, potentially saving a patient’s life.