English business writing is an important and challenging course for English as Foreign Language (EFL) students since it is not only related to English writing skills, but also to business knowledge. Context-game based learning seems to be a good approach to situating students in a meaningful and interesting practicing environment, which could improve their learning motivation and interest. However, without interacting with the teacher and peers, the effectiveness of game-based learning could be limited. In this study, a flipped contextual game-based learning approach was proposed to cope with this problem; moreover, a mixed methods research approach was used to analyze the writing performance, writing errors, and reflective content of the students who learned with the proposed approach and those learning with conventional contextual game-based learning. The experimental results revealed that the flipped contextual game-based instruction was able to enhance the students' English writing performance. It was also found that those students with the flipped learning approach had fewer writing errors than those learning with the conventional approach. Moreover, by analyzing the students' reflective content, the benefits and challenges of flipping the classroom are reported. These findings could be valuable references for those who intend to conduct effective flipped contextual game-based learning with learning management systems to motivate students' game-based learning and to improve their language learning performance.