This research aims at proving whether or not the application of Audio-Articulation Method (AAM) can enhance the ability of the eleventh grade students of SMA Negeri 1 Palu to pronounce interdental sounds. The samples are XI Science 1 students as the control group and XI Science 2 students as the experimental group. They were selected by using purposive sampling technique. The researcher employed quasi-experimental research design where the two groups were given pre-test and post-test. There are two variables; the application of AAM as the independent variable and the students' pronunciation ability as the dependent variable. The result of the research shows that the application of AAM gives significant improvement to the students' ability to pronounce the interdental sounds. The mean score of the experimental group before the treatment is 8,93 while the control group's is 10,19. After the treatment, the mean score of the experimental group is 67,3 and the control group's is 19,2. It is also shown that the t-counted (8,565) is greater than the t-table (1,999). Thus, it can be concluded that the hypothesis is accepted. In other words, AAM can enhance the ability of the eleventh grade students to pronounce interdental sounds.