Resistance of foodborne pathogens to low pH environments is often considered one of important determinant of disease， which helps bacteria pass through the stomach and can cause illness at very low infective doses. The research progress of three major amino acid decarboxylase systems in Escherichia coli， namely glutamic acid decarboxylase system， arginine decarboxylase system and lysine decarboxylase system were summarized. The primary objective is to elucidate the acid-resistant mechanism of foodborne pathogens.