Pronunciation is truly important in English speaking activity since it can highly influence the meaning of utterances. If someone makes error in pronouncing some words in a sentence, it can disturb the communication, even it can be one of the factors which can lead to the conversation breakdown. In fact, there are many Indonesian students who find difficulties in comprehending English pronunciation because the words they have heard or spoken are often different with their written form. To cope those problems, the researcher uses Tongue Twister as a technique to improve EFL students’ pronunciation. By using this technique, it hopefully can make the students more enthusiastic and easier to master pronunciation of English especially on segmental features and some parts of suprasegmental features (word stress and sentence stress). This research has purposes: To describe the implementation of Tongue Twister technique in improving EFL students’ pronunciation. This research was classroom action research done through two cycles. The participants of this research were the tenth grade students of SMA Unggulan Nurul Islami Semarang in the academic year of 2015/2016. The data were obtained by interviewing teacher, observation, test, and documentation. The result of the study showed that there was improvement of students’ pronunciation after being taught by using Tongue Twister technique. This was proven by the students’ score that improved in every cycle. In the first cycle, the students’ average score was 71,25 and in the second cycle students got 84,47. Based on the observation checklist result showed that students gave their positive responses by becoming more enthusiastic and actively involved in the group work. The result of this study is expected to be information and new reference technique for teaching English pronunciation.