Environmental Public Policy in this research is defined as the bottom-up policy that isbuilded by local people for people in community to protect and conserve their localnatural resources and manage environment. It is so different from the common publicpolicy that created from top-down or by the government sector. Currently, this kind ofpublic policy is created and managed in many local places in Thailand. The researchfound that the first factor is the local resources were destroyed tremendously and theresult is the worse environment. The local people who are leaders or group ofleaders can observe a worse environment and try to protect natural resources fromdamage and conserve the environment immediately. After that the people incommunity will participate and join together as network both inside and outside area.The development process to protect the local resources is beginning. At last thenetwork is expanded and need more knowledge from higher technicians both in thegovernment and private sectors. They are learning by doing together until they cancreate simple local regulations to control each other but not obstruct the main law.There is management by participation such as a foundation. Finally, the local publicpolicies such as knowledge and ideology are inherited to the community descendants.This operation becomes to be public policies in the people sector.In this research, a Policy Cycle has been developed according to policy science toanalyze. The Public Policy Cycle is composed of seven steps which the researchersynthesized from many theoretical concepts. There are policy problem, policyformation, policy formulation, policy implementation, policy outcome, policy evaluationand policy feedback and have been used to analyze five specific community-basedenvironmental policy cases of Hak Muang Nan Group; Nan Province, Mae Ta ChangDrainage Basin Project; Chiang Mai Province, Thai-German Upland DevelopmentProject; Chiang Rai Province, Wana Kaset Banna Isan Group; Chachoengsao Province,and Coastal Resource Administration; Trang Province. The result can explainaccording to the policy cycle theory. According to this analysis, elements of aneffective growth of community-based environment public policy are 1) an awarenessof the destroyed environment; 2) a leader or leader group who thinks about socialawareness; 3) a leader or leader group which starts initiate local communitydiscussion informally; 4) ability to initiate work immediately; 5) ability to revise and seek knowledge; 6) effective networks; 7) sharing the knowledge to outside networks;8) seeking for resources to manage the policy; 9) spreading knowledge andresponsibility to other networks and 10) building new generation to learn theenvironmental knowledge. However, prerequisites for a community-basedenvironmental public policy development are that leaders 1) must have new paradigm;2) must have a public consciousness attitude; 3) willing to invite external assistancefor help; 4) develop local regulation and 5) the regulation and rule of the communityshould be not contrary to state policy law.