Human Behavior and Social Environment is the most basic course in the Department of Social Work. Mainly from the perspective of social environment to understand the process of human behavior change and growth. There are abundant similar textbooks abroad, but relatively few in China. How to combine foreign theoretical achievements with domestic concrete reality is the most puzzling problem for the author. In the process of writing, the author hopes to make some useful attempts, but still finds it difficult. When expounding the social influence factors of human behavior, the author emphasizes the role of family, center and sex, which are also some important topics in our real life, but they are relatively easy to be ignored or avoided. As for the school, unit, community, organization, social system and other factors, some are well known, some are inserted in relevant chapters, and there is no special chapter. In terms of specific writing ideas, there are many similar textbooks abroad. The author adopts a common and acceptable general method, which is developed step by step according to the growth process of people and described by questions.