English has become the world's international language, used for international communication mostly among non- native speakers of other languages. It is undeniable that Thai students do not speak English fluently and accurately enough although they have studied English for many years. The speaking and listening ability in English of Thai students has been minimal because they have few chances to practice speaking English in or outside classrooms. The students are trying to translate from Thai to English. They tend to carry the intonation, phonological processes and pronunciation rules from Thai into English speech. They may also create innovative pronunciations for English sounds which are not found in the speaker’s first language. Similar to ESL learners of other contexts, Derwing and Rossiter (2002) surveyed 100 adult ESL learners in Canada to learn about their pronunciation difficulties and strategies. Over 50% of the learners reported that pronunciation contributed to breakdowns in communication