Securitization is a very important category and a pivotal step for understanding the concept of non-traditional security and the extended connotation of security . The course of securitization of ecological issues is most striking . Through political and scientific agendas , it clarifies in practice how ecological issues have been upgraded from public ones to security ones and how the ecological values are objectively being threatened .At the same time ,it theoretically represents a third level to understand security , i .e ., the intersubjectivity outside the levels of objectivity and subjectivity , bringing security issues into a new state of interactions between 'security ,''sense of security'and'securitization'.