Hypochlorous acid (HOCl), a well-known universal disinfectant in clinical practice, plays important roles in immune systems of animal and human bodies. For understanding the roles of HOCl in living systems, a number of approaches, including chemiluminescence, colorimetric, electrochemical and chromatographic methods have been explored. For the detection of HOCl in live organisms, cutting-edge techniques, such as fluorescence/phosphorescence molecular probes, responsive nanoprobes, Raman and activatable photoacoustic sensors, have also been developed recently. In this review, the recent advances in the development of bioanalytical methods for detection of HOCl in environmental and biological specimens were summarized. More specifically, traditional techniques for assay of HOCl in bulk solution were initially discussed, and then fluorescence molecular probes, phosphorescence probes, responsive nanoprobes and other methods for HOCl detection were reviewed, which gives an overview of the developments and applications in bioanalytical methods for HOCl detection. •Production and functions of HOCl in biological systems were introduced.•Recent development of bioanalytical methods for HOCl analysis was reviewed.•Performance for the detection of HOCl by fluorescence probes were compared.•Challenges and future outlooks for the development of bioanalytical methods for HOCl were discussed.