Pharmacology is one of the indispensable and professional basic courses for medical students based on physiology, biochemistry, pathology and pathogenic organisms. Pharmacology is a subject which studies the principles of interactions between drug and living organism which includes human body, tumor cells and microorganisms and its mechanisms. Pharmacology introduces the basic theories and principles of drug and then clinical relevance. The most important task of pharmacology is to explain the action and its mechanisms of the drug, to provide the theoretical basis for clinic, enhancing the drug efficacy and reducing adverse drug reaction. These studies lay a solid foundation for clinical courses.