Bacterial activity detection is the key to inspection, evaluation and preservation. Rapid, sensitive, specific and accurate bacterial activity detection methods are very important. At present, bacterial activity can be measured according to the principles of bacterial growth and reproduction ability, metabolic ability, membrane integrity, and replication and transcription ability. Different detection principles will have different detection methods, plate culture counting method is the most classic activity detection method, Propidium Monoazide combined with Quantitative PCR(PMA-qPCR), fluorescent dye-combined flow cytometry, single-cell Raman analysis technology is the new application of instruments. With the continuous development of science and technology and the demand of bacterial activity detection, optimized bacterial activity detection methods are emerging in an endless stream, but different bacterial activity detection methods have different advantages and disadvantages. In this paper, the principle, method, application, advantages and disadvantages of bacterial activity detection were described, and the application of bacterial activity detection method in bacterial inspection and preservation was discussed.