A sensing device including a semiconductor substrate, a filtering structure and a sensing structure is provided. The semiconductor substrate has a sample excitation region and an optical sensor region. The optical sensor region laterally encircles the sample excitation region. The filtering structure is embedded in the semiconductor substrate. The filtering structure is located in the sample excitation region and has a sample containing portion. The sample containing portion is adapted to contain a sample and receive an excitation beam. The sensing structure is embedded in the semiconductor substrate. At least a portion of the sensing structure is disposed in the optical sensor region and the sensing structure at least laterally encircles the filtering structure. After the excitation beam is transmitted to the sample containing portion along a direction perpendicular to a surface of the semiconductor substrate and excites the sample, the sample is adapted to emit a signal beam, and the sensing structure is adapted to sense the signal beam.