Abstract: Under the framework of systemic functional grammar, Matter refers to circumstantiation of projected messages, which is realized as prepositional phrases. However, the Sydney model and Cardiff model analyze the grammatical unit differently. The paper discusses the rationality of the two models from multiple dimensions including analytical principles, stratification, the interaction between textual and experiential functions, rank shift and the related phenomena in Chinese. It is found that the concept of “matter” proposed in Sydney model is of high generality. It is advised, in light of the analysis of the Cardiff Model, that matter-phrase be further divided into two sub-categories, namely, inner matter and out matter.