Rhizoma Coptidis was widely used to treat dispersion-thirst since ancient times,and it is called “dispersion-thirst panacea” by Professor Tong Xiaolin.Professor Tong applies Rhizoma Coptidis well with the treatment of diabetes and its complications.He has accumulated a lot of experience during the many years of clinical practice.This paper expounds the clinical application，dose-response and toxicity of Rhizoma Coptidis respectively.Clinical application of Rhizoma Coptidis is summarized by Professor Tong as follows:regulating the spleen and stomach by opening with acridity and downbearing with bitterness,modulating intestinal microflora by clearing heat and dring dampness,stabilizing arrhythmia by clearing heat and draining fire and treating furuncle and carbuncle by clearing heat and resolving toxin.In addition,we should pay attention to the scientific compatibility of Rhizoma Coptidis with other herbs and make sure the rational dosage in clinical practice.Also,how to take decoctions and to balance efficacy and safety are also very important.