AIM: We establish a suitable distinguishing reaction of nitrate and nitrite in Chinese traditional medicine containing reduction agents. METHODS: In different concentration solution of sulfate acid,we study on the distinguishing reaction,by paralleling samples with negative samples and positive samples. RESULTS:The nitrite and sample containing nitrite react with ferrous sulfate reagent from brown in 50%-5% solution of sulfate acid;The nitrate and sample containing nitrate react with ferrous sulfate reagent from brown in ≥25% solution of sulfate acid.The negative sample and sample without nitrite and nitrate does not react with ferrous sulfate reagent in 50%-5% solution of sulfate acid. CONCLUSION: The thin sulfate acid-ferrous sulfate reagent-nitrate ditinguishing reaction can be used to distinguish nitrate and nitrite in Chinese traditional medicine containing reduction agents.