An Investigation of Factors Causing English Mispronunciation of Students in English for International Communication

English has been recognized as a lingua franca in different aspects of communication such as international business, academic context, science and technology. Despite the constant efforts of developing English education in Thailand, studies have shown that the achievement of Thai students was still unsatisfactory. Additionally, previous studies revealed Thai EFL learners faced a number of difficulties in pronunciation and speaking. The purposes of this study were to investigate the levels of the factors and the most and least factors causing in English mispronunciation of 2nd and 3rd year students in EIC at RMUTL Tak campus. Fifty-one students were purposively selected from EIC of 2nd and 3rd year in 2019. The research instrument included questionnaire and adopted Likert scale for data analysis. The results found that 2nd and 3rd year students in English for International Communication (EIC) Program evaluated the factor causing in English mispronunciation found that 1) the first language interference factor have the highest mean value 2) phonetic ability factor 3) experience in studying English factor and 4) motivation factor have the lowest mean value.