A method of determination of bacterial endotoxin in pharmaceutical intermediate 7-ACA was established. According to 《China Pharmacopoeia 2010 Edition》 "(two)" appendix XIE, the bacterial endotoxin was determined and the results were judged. The results showed when the sample of 1.25 mg/mL had no interference to the test of the bacterial endotoxin. The method could be used in determination of bacterial endotoxin in the pharmaceutical intermediate 7-ACA.