With the rapid development of probiotics, people are more and more attention on the probiotic efficacy of lactic acid bacteria as a class of probiotics. At present, freeze-drying preparation of lactic acid bacteria powder is one of the main aspects of its preparation process. However, the freeze-drying process will inevitably cause different degrees of damage to its bacteria, thus affecting the number of viable cells, the fermentation process will have an impact on the number of freeze-dried bacteria. The effect of fermentation process and freeze-drying process on the frost resistance of lactic acid bacteria was analyzed. Through the anal. of these related factors, in order to improve the frost resistance of lactic acid bacteria , and then improve the level of viable bacteria to provide new ideas.