Abstract: In recent years, scholars began to focus on multimodal discourse analysis of comics, but mostly they conduct a general analysis of the three metafunctions:representational function, interactional function and compositional function, which cannot fully reveal the ideational meaning of the comics.On the other hand, most of the researches take political comics as the object of analysis, and less research is on the comics in other genres.Therefore, this paper, based on the multimodal discourse analysis, takes a comic strip from PHD Comics as a case study and explores the representational meaning reflected from this comic strip, hoping to promote the application of multimodal discourse analysis to the study of the comics.