This present study attempts to investigate the effect of Task Based Language Teaching on the teaching practice of pre service English teacher. To achieve the objectives, the researcher used one group of the student in the academic year 2015/2016 without control group for comparison. Ali (2016) describes the scheme of one group pre-test post-test design. The subject of the research was one class of 6C who got Micro Teaching before doing PPL (teaching internship) in the following semester. The total number of subject in this study was 25 students. The data were collected through Performance Test of teaching practice as instrument of the research. After conducting the pre-test of Performance test of teaching practice and giving the treatment by using TBLT. The post test was conducted by the researcher to the students in order to know the teaching Practice of the Students in the academic year 2015/2016 after being taught by using Task Based Language Teaching. The researcher got that the result of the post test is higher than the pre-test. The highest score is 86.36 and the lowest score is 77. From the data, the mean of teaching practice of the EFL Students in the academic year 2015/2016 after being taught by using Task Based Language Teaching is 81.36 and the standard deviation is 2.360791. It is higher than before being taught by using Task Based Language Teaching. The mean after is 81.36 and before is 75.28. They have more improvement in doing their post-test after being taught by using Task Based Language Teaching twice in their class. The result can be categorized as good criterion. The teaching practice of the Students in the academic year 2015/2016 before and after being taught by using Task Based Language Teaching is different. According to the mean of both tests, the result of post-test is higher than pre-test. It happens after the researcher gave the students twice treatment using beneficial teaching strategy in solving their problems on teaching practice. The researcher used t-test formula, the result of the significance difference of the teaching practice of the EFL Students in the academic year 2015/2016 before and after being taught by using Task Based Language Teaching is 8.90 was higher than t-table. The level of significance of 5% is 2.06. It is gotten from the degree of freedom (df) = N – 1 = 24, so then t0 is higher than t-table (t0 > t-table = 8.90 > 2.06. So, it can be concluded that there is a significant difference of the teaching practice of the Students in the academic year 2015/2016 before and after being taught by using Task Based Language Teaching. Using TBLT teaching strategy, the teachers used some beneficial task and varieties activities that make the class more life. A successful Task-Based lesson requires from teachers: good preparation, creative atmosphere, and clear instruction. On the other hand, it requires from students: good preparation, participation, and using target language. Moreover, the result shows that it has positive effect. It makes EFL teachers implement TBLT as follows: the appropriateness of TBLT for all types of groups, TBLT improves learners’ interaction skills, TBLT enhances learners’ intrinsic motivation, TBLT also supports collaborative learning.