In the era of mobile internet, the rapid development of smart phones and other terminals has brought challenges to the teaching management and quality of colleges and universities. The innovation of teaching reform in colleges and universities should focus on the research and practice of mobile learning mode. Mobile learning mode is not a simple combination of technology and education, but a reform of teaching concept. In this paper, in the teaching practice of Literature Retrieval, we use the "rain classroom" developed by Tsinghua University to study the mobile learning mode.