非正式群体是指人们在活动中自发形成的、不被任何机构或单位所承认的群体。这种现象在中学班级内的青少年身上出现的尤为频繁。不难发现,外界对青少年非正式群体的认同情况影响着青少年自身及非正式群体在青少年群体内的发展。本文中,对中学班级内青少年非正式群体的特点及其认同和发展进行了介绍。 Informal groups refer to groups that are spontaneously formed by people and are not recognized by any institution or organization. This phenomenon is particularly frequent among teenagers in the middle school class. It is not difficult to find that the outside world’s identification with informal groups of young people influences the development of young people themselves and informal groups within the adolescent groups. In this article, the characteristics, identity and development of informal groups of young people in middle school classes are introduced.