As a part of vocabulary learning, the idiom is an important part of language teaching. This study is to investigate whether conceptual metaphor can promote idioms’ teaching and learning or not. In the course of study, we make use of a combination of qualitative and quantitative analysis, collecting data through the questionnaire survey and do experiments in teaching and learning idioms. We get the conclusion: the T value of the experimental group and the control group is p<0.05, the pre-test and post-test values is p<0.05. It is feasible to apply the conceptual metaphor in idiom teaching and learning.