The vital role of English teachers' involvement in shaping characters of students makes a study on Genre Approach in Indonesia is so necessary. This research discusses the Genre -Based Instruction in junior and high schools. It studies the kind of change and attitudes which could play an important role in determining whether a teacher chooses to support or resist a change. TheEnglish teachers' willingness in the change process leads to a major influence on attitude. The Genre -Based Instruction needs the awareness of English teachers to get similar perceptions and interpretations to those of government and curriculum designers have. The involvement of English teachers not only in the development process of the Genre -Based Instruction but must also commit tothe English genres as the core of learning process.