As a multimodal media, graffiti are regarded as the systematic means for expressing meaning. Interpersonal meta-functions and interactional meanings in L1 and L2 graffiti have drawn the attention of linguistics researchers. Likewise, the present descriptive contrastive critical discourse analysis was conducted to identify the interpersonal meta-functions and interactional meanings in 360 randomly selected pieces of graffiti, 180 in English and 180 in Persian. The English data were collected from Vancouver, Canada, and Sydney, Australia; the Persian data were collected from Tehran and Tabriz, Iran. The researchers took advantage of Halliday’s interpersonal meta -function analysis (Halliday & Matthiessen, 2004; Halliday & Matthiessen, 2014; Thompson, 2014), and Kress and Van Leeuwen’s (2006) framework to identify the interpersonal meta-functions and interactional meanings, respectively. Consequently, the graffiti devoid of clauses and pictures were removed, and 27 English and 26 Persian clauses along with 22 Persian and 18 English pictorial graffiti were selected as the data of the study. To describe, interpret, and explain the data, we took advantage of Fairclough’s (1995) framework. The results manifested similarities and differences in terms of interpersonal meta-functions and interactional meanings in the English and Persian graffiti. The findings underscore the need to raise teachers’ and learners’ awareness of graffiti, interpersonal meta-functions, interactional meanings, and critical discourse analysis in English as a foreign language (EFL) contexts.