For decades, multimodality, an intrinsic attribute of discourse, has long been neglected in discourse analysis. Adopting the theoretical framework of visual communication grammar by Kress and van Leeuwen, which grew out of Halliday's systemic functional grammar, this paper makes a detailed social semiotic analysis of the three-fold metafunctions of the visual and verbal modes of one of the No Smoking Day print advertisements. The analysis shows that these two semiotic modes complement and supplement each other to add to the denotation and connotation of the discourse.