The ingredients of cosmetics were complicated, and the nutrition in them were a good medium for the growth of microbes to lead to microbial pollution. In the testing of cosmetics, proportion exceeding the standard of the fecal coliform was the highest. The concept, biochemical characteristics and detection method of the fecal coliform were discussed. Detection could be done according to the biological characteristic of the fecal coliform, picking suspicious colonies to do a smear of gram stain under the mirror.The results showed that if there were typical colonies on the plate and they were confirmed to be gram negative bacillus brevis, and the test of indole was positive, there were fecal coliform in the detected products.