This paper first provides a review of Deliberate Metaphor Theory (DMT) by examining it with reference to a three-dimensional metaphor model and then discusses its strengths and weaknesses. The three-dimensional metaphor model holds that metaphor is more than a linguistic and conceptual phenomenon, and it also relates to communication. With reference to the three dimensions of language, thought and communication, the paper makes clear what Deliberate Metaphor is by examining the following four pairs of metaphors: Deliberate Metaphor and Non-deliberate Metaphor, Deliberate Metaphor and Conscious Metaphor, Deliberate Metaphor and Conventionalized Metaphor, Explicit Metaphor and Implicit Metaphor. The paper argues that DMT has paved a new way to study metaphor, and it made great contribution to bridging discourse analysis and cognitive linguistics, and psycholinguistics and sociolinguistics.