Abstract: The consumption of fish and its products has risen sharply in recent years due to their high nutritional value. However,due to the large amount of water contained in fish bodies,the fragility of fish tissues and the effects of enzymes and microorganisms make fish and their products easily perishable,resulting in a rapid decline in fish quality. Therefore,the rapid and effective detection of fish freshness is of great significance to the future food industry. This paper introduces the principles and applications of techniques for fish freshness detection,including biosensor technology(electrochemical and enzyme biosensors),sensory bionics(electronic nose,electronic tongue,colorimetric sensor array,and computer vision technology)and spectral techniques(visible/near-infrared spectroscopy,hyperspectral imaging,and fluorescence spectroscopy),and summarizes the advantages and disadvantages of these methods,and makes a prospect for the research focus and development trend of the rapid detection technology of fish freshness in the future.