The application of marketing planning course is intended to provide students with integrated knowledge of the marketing management process. The purpose of this study is to help improve the learning condition of low-achieving students in marketing planning curriculum and to understand how well remedial instruction associated with the curriculum design in marketing planning affects student learning condition. Twelve business-majored students were selected as purposive sampling and were asked to fill in questionnaires. This study used paired-samples t-test and in-depth interview to investigate students' pre- and post- learning effect. The results showed that the remedial instruction in marketing planning is effective to improve low-achievers' learning achievement and academic performance.