In view of college students' inactiveness in English learning and low efficiency of English for Special Purpose (ESP), this study throws some light on the reform of college English teaching mode based on constructing ESP corpora, which has been put into practice. The effect of this college English teaching mode based on constructing ESP corpora is analyzed by questionnaire and course examination. And the result illustrates that such teaching mode is quite effective in promoting students' interest and ESP level despite some drawbacks.