The invention relates to a production method for a streptococcus thermophilus viable bacteria preparation, belonging to the field of microbial technology and particularly relating to a liquid anaerobic fermentation production method for a streptococcus thermophilus micro-ecological preparation. The production method comprises the following steps of taking the streptococcus thermophilus as the fermented strain, inoculating into an optimized liquid medium, cultivating for 16-20 hours at 40-42 DEG C, putting the fermentation liquid in a tank and measuring the viable bacteria quantity, adsorbing the fermentation liquid through vegetable starch and drying, after treatment by polyethylene glycol (PEG) 4000 and sodium polyacrylate, drying, smashing and packaging, and preparing the streptococcus thermophilus preparation with stable activity. The production method has the advantages of completing high density fermentation of the streptococcus thermophilus through a common fermentation tank, being simple in operation, having stable effect and low energy consumption, using no equipment such as a centrifugal machine and a freeze dryer and the like, lowering the production cost, and improving the production efficiency.