Abstract: The compatibility of Chinese medicine and western medicine is becoming more and more common， but the changes in efficacy and adverse reactions of drug interaction caused by drug interaction has attracted more and more attentions. This article mainly expounds the interaction between Chinese medicine and western medicine in four aspects: absorption， distribution， metabolism and excretion of drugs. Among them， Chinese medicine can affect western medicine absorption by changing the gastrointestinal pH， gastrointestinal motility and gastric emptying time changes， the chelate complexes， and the precipitate formation; it can change the distribution of the main active ingredients in western medicine; it can change liver microsomal enzyme and non-microsomal enzyme to affect western medicine metabolism， the western medicine excretion through the bile and kidney， and western medicine transport process in vivo by P-glycoprotein. The article explains the pros and cons of Chinese medicine and western medicine from the pharmacokinetic process， which provides the basis for the clinical guidance for the combination therapy of Chinese medicine and western medicine.