The purpose of this study was to evaluate grade 12 EFL textbook listening tasks and teachers' implementations of listening tasks on the basis of CLT (Communicative Language Teaching). A descriptive research design was used. The subjects of the study included a Grade 12 EFL textbook, 65 grade twelve students, and four grade twelve English teachers. The simple random sampling technique and the comprehensive sampling technique were used to select the participant students and teachers, respectively. As data collection tools, document analysis, questionnaires, and observations were used. Then, the book was evaluated using the checklist for communicative tasks, and the data obtained from participant teachers and students were analyzed quantitatively and qualitatively. Data from the document analysis was analyzed qualitatively while data from the questionnaire and observation were analyzed quantitatively. The data included both authentic and contrived items; the number of contrived items exceeded the authentic ones, and they were appropriate to the goals of the tasks. All the activities presented in the listening tasks were designed in accordance with the input data. The variety of listening activities was not enough. The activities include a limited variety of active learning methods. Moreover, most of the activities did not include the three stages of language learning; pre-task, while-task, and post-task. The teachers did not appropriately implement the tasks. The roles of learners and teachers in the listening tasks of the book were appropriate. However, these roles were not clearly stated in the book. The number of individual work activities was relatively high compared to the whole class and group activities. More number of pair and group work activities exceeding individual activities should be include in the listening tasks