Quorum sensing (QS) is a bacterial communication system that depends on bacterial density and is closely related to bacterial pathogenicity and drug resistance. QS signal molecules are an important substance basis for QS system to regulate various cellular processes of microorganisms. The identification and detection of QS signal molecules is an indispensable link in the exploration of the regulatory mechanism of bacterial QS system. It is of important reference significance for the interaction, efficient detection and mechanism analysis of microorganisms such as bacteria in the fields of life science and pharmacy. It is illustrated that the photoelectric sensing detection is of great potential for the real-time detection of QS signal molecules with its high sensitivity and diversity of methods. Combining with molecular imprinting, biological receptor recognition, magnetic separation and so on, photoelectric sensor could provide more efficient means of detection. In this paper, the types of QS signal molecules and common QS systems were briefly introduced, and then the photoelectric detection methods and technologies of QS signal molecules were summarized. The sensitive media, sensing interface, sensing mechanism and testing effect of photoelectric sensing detection were discussed in details. The optical analysis techniques were of a wide range of applications in the detection of QS signal molecule in biological samples. Fluorescence detection method has high sensitivity in quantification of signal molecules, and fluorescence imaging method can provide real-time in situ observation of bacterial QS process. Surface enhanced Raman scattering (SERS) spectral analysis technique could provide molecular fingerprint information of targets in the QS process of some biological samples. Electrochemical detection techniques could dynamically monitor QS signal molecules through the changes of electrochemical signals. Meanwhile, much more attention had been paid to microfluidic analysis technology, because it was taken as a favorable platform for the in-situ monitoring of bacterial QS signal molecules and QS process by the way of combining the photoelectric sensors and microfluidic control.