The trend of flipped class" mode in college teaching are discussed in this paper, based on the in-depth analysis. Their position as teaching method and mode are also clarified. In particular, although the subjectivity of students in the teaching process is emphasized in teaching mode, the dominance of teachers in the whole teaching process is not denied. The successful practice of "MOOC+ flipped classroom" teaching model in theoretical mechanics course of Guangzhou university shows that the willingness to learn independently has a very important influence on the teaching effect of this model. The difference of learning effect before class and the knowledge base are the biggest difficulty to implement this teaching model. The master and control of the teaching process is the fundamental guarantee for the effectiveness of the "MOOC+ flipped classroom" teaching mode.