The United Nations system and governments, every year on June 5 this day to carry out various activities to promote and stress the importance of protect and improve the human environment.
The United Nations environment programme (unep) announced at the beginning of each year the world environment day theme, and published in the annual world environment day annual report on environmental conditions. During this period of China's state environmental protection administration issued the environment bulletin.
From June 5, 1985, China began to commemorate the world environment day activities, with "youth population, environment" as the theme. Since then, every year on June 5, the country hold commemorative activities. 1993 Beijing was elected to the celebration of the city, its theme is "to break the cycle of poverty and environment". Released in April 2014 revision of the environmental protection law of the People's Republic of China, article 12: for environment day on 5 June every year.
1972年6月5日联合国在瑞典首都斯德哥尔摩召开了联合国人类环境会议，会议通过了《人类环境宣言》，并提出将每年的6月5日定为“世界环境日”。同年10月，第27届联合国大会通过决议接受了该建议。世界环境日，是联合国促进全球环境意识、提高政府对环境问题的注意并采取行动的主要媒介之一。
联合国系统和各国政府，每年都在6月5日的这一天开展各项活动来宣传与强调保护和改善人类环境的重要性。
联合国环境规划署在每年的年初公布当年的世界环境日主题，并在每年的世界环境日发表环境状况的年度报告书。中国国家环保总局在这期间发布中国环境状况公报。
中国从1985年6月5日开始举办纪念世界环境日的活动，以“青年人口，环境”为主题 。自此之后，每年的6月5日全国各地都要举办纪念活动。1993年北京被选为举办庆祝活动的城市，其主题是“打破贫穷与环境的怪圈”。2014年4月修订公布的《中华人民共和国环境保护法》第十二条：每年6月5日为环境日。
