This study is aimed to investigate the implementation of mind mapping strategy to teach writing in IELTS preparation class. In particular, there were four objectives guiding the conduct of this study: (1) to describe the implementation of mind mapping strategy, (2) to investigate the students' responses, (3) to examine the problems, and (4) to explain the solutions of implementing mind mapping strategy in IELTS writing class. It was a descriptive qualitative study on 20 students of IELTS preparation classes. Those students were divided into 6 classes based on their level after taking IELTS placement test. There were 3 teachers who taught 2 classes each. The data were collected by using classroom observations, students' questionnaire, teachers' interview, and document analysis. Those were analyzed in descriptive qualitative method, though there was simple quantitative analysis on students' questionnaire. In conclusion, this study revealed four results regarding the particular objectives about implementation of mind mapping strategy in IELTS writing preparation classes.