Abstract: In order to reduce visible foreign matters in penicillin products and improve product quality, the hypothesis that the visible foreign matter in products is the increase of pyrogen in products was put forward based on the analysis of visible foreign matter in products and production process, combined with the theoretical knowledge of pyrogen properties and removal methods. Based on this design test, by increasing the pyrogen removal capacity in the production process, that is, the amount of activated carbon, the goal of reducing visible foreign substances in the product could be achieved. Taking the amount of activated carbon as a variable, the experimental comparison showed that the amount of activated carbon is directly related to the visible foreign bodies in the finished product. With the increase of the amount of activated carbon, the number of visible foreign bodies in the product gradually decreases, and the optimal amount of activated carbon is determined to be ≥27 g/ billion. Through the process improvement, the visible foreign matter in the product is reduced, and the optimal dosage of activated carbon is confirmed.