Teaching methods used to be a central concern of the language teaching profession. Although changed understanding of the nature of language teaching in recent decades has somehow reduced the significance attached to teaching methods, how to teach a foreign/second language effectively continues to be an important aspect of language teaching. Language scholars, however, have tended to focus their attention on theoretical stipulations of teaching methods without giving empirical data from actual teaching contexts. Language teachers, on the other hand, tend to lack both theoretical knowledge of language teaching methods and the consciousness to adopt systematic ways of teaching in their classrooms. The current study is designed to explore the implementation of task-based language teaching (TBLT), one of the most recommended teaching methods in foreign/second language teaching, in a secondary school in Macau, in order to find out the practical usage of this method and its concerned challenges so that feedbacks from frontline teaching and related suggestions can be provided. A case study method was adopted in the current research, and data were gathered through class observations, semi-structured interviews, and questionnaires. Participants of the study included teachers and students selected from three junior secondary grades of the school under study (School X). From the data resources, the study finds that teachers in School X did not use TBLT but use task-supported teaching method instead. Tasks used by language teachers proved to be effective in motivating students and increasing their interest in learning English. Besides, how frequently tasks were used is depended on the types of English lessons. Usually, tasks were more frequently used in English Conversation lessons than General English. Unsuccess in adopting TBLT in School X resulted from the difficulties that language teachers encountered in III their teaching, including the state of students, teachers’ development, class size, conflicts between teachers and the administrative authorities and the deep rooted exam culture, etc. The study offers practical suggestions to ELT (English language learning) stakeholders and the future research. To increase the effectiveness of English language teaching through the implementation of teaching methods as one of the means, school authorities, teachers and students should cooperate well. For the future research, research ethics, depth in research and improvement in research methodologies are the important aspects which should be paid great attention to.