The purpose of this study was to determine whether the use of ELSA Speak is effective in improving students' pronunciation accuracy. This research was carried out on young learners of My liberty with 13 students as research sample. By conducting quasi-experimental research with one group pre-test and post-test design, this research concluded that the use of ELSA Speak is effective in improving students' pronunciation accuracy. The result of hypothesis testing shows that fcount= 5.23, with the degree of freedom 24 and the level significance a. = 0.05. The researcher also found that the value of t1able 2.04. Therefore, the use of ELSA Speak is effective in enhancing students' pronunciation skill, significantly as the result i:oun1>ttable or 5.29 > 2.08. So, the conclusion is the use of ELSA Speak application in teaching and learning process is effective in enhancing the students' pronunciation accuracy. Besides that, by calculating the data of pre-test and post-test, the researcher found out that there is an improvement of the pronunciation ability of students the before and after taught by using ELSA Speak during 4 times treatment. Mean score in the in the post-test is higher than in pre-test. As shown in findings, the average of students' score in pre-test is 63,15 while the average of students' score in post-test is 103, 62. It means the range of students' score in pre-test and post-test is 44,47.