The quality of six commercial brands of lactic acid bacteria products on Beijing Market was studied.The results showed that of all tested samples,the protein content,the fat content,the acidity,the number of lactic acid bacteria,E.coli,yeast and mould were in line with National Standards.The calcium content of four kinds of yoghurt was much larger than that of activated Lactic acid bacteria beverage.The largest number of lactic acid bacteria in four kinds of yogurt turned up in the eighth day,while the number of two kinds of lactic acid drinks reached the peak for the first day.In conclusion,six brands of lactic acid bacteria products are qualified,consumers can set their mind at rest about the purchase and drinking of the lactic acid bacteria products.