Under the background of the reform on the college English curriculum in Chineseuniversities, the paper researches on the teaching theories of CBI and ESP. A CBI-based college ESP teaching mode has been designed and carried out. The paper analyzes the teaching characteristics, implementing principles and steps of theESP teaching mode. And it also expounds that the teaching mode not only can meet the needs of students' professional learning and disciplinary development, but also it is effective in motivating students and improving students' English academic ability.