Dermatovenerology is a broad and comprehensive second-level clinical disapline with relatively independent professional knowledge system and research direction. Dermatovenerology consists of dermatology and venerology. Dermatology is a science dealing with skin and related diseases. Its contents include not only the structure and function of normal skin and appendage， but also the etiology，pathogenesis， clinical manifestation， diagnosis， treatment and prevention ofvarious skin and appendage related diseases. Venerology is a science that studies sexually transmitted diseases， including pathogenic microorganism， pathogenesis， transnussion route， clinical manifestation，diagnosis， treatment and prevention of various sexually transmitted diseases. The book aims to aid undergraduate medical students to establish the principal conceptions of the structures and functions of skin， and readily to understand how the skin diseases occur and develop， and how to treat and prevent these diseases.
　　I am grateful for the editors. With the collaborations of the team members， we gained rich experience in tutoring the international students， which is beneficial for me to write the book. I also thank those who provide the aids in publishing this book， including Overseas Education College ofjiangsu University， the editor Ms. Zhong Hui and Dr. Ji Jiang of the Second Affiliated Hospital of Soochow University， Dr. Chen Xiaodong of the Affiliated Hospital of Nantong University， Dr. Zhong Liansheng of the Afliliated Hospital of Xuzhou Medical University， Dr. Chen Juping of the Affiliated Hospital of Yangzhou University， Mr. Abdur. rahim. zar and Mr. Michael Adu-Frimpong for their reviews and comments of the manuscript.