As varieties of the Chinese language, Mandarin and Cantonese are both tonal in nature and involve pitch cues for distinguishing characters and words. Chinese as a second language (CSL) learners often find Chinese tones difficult to grasp, especially for those at the preschool stage. In Hong Kong, Cantonese is the dominant variety of Chinese for daily communication and serves as the medium of instruction in local kindergartens, whereas Mandarin is used in Chinese language teaching in international kindergartens. Children’s songs are widely used to foster preschoolers’ CSL learning in the aforementioned settings. With adequate phonological input in a pleasurable learning environment, such an approach helps facilitate tone perception, which is key to the development of prosodic competence for better facilitation of reading comprehension. However, the tone-melody mismatches in children’s songs and their negative influence on CSL learners’ tone learning have long been underestimated. This chapter looks into the problems concerning teaching CSL through children’s songs from a comparative perspective. Based on a contrastive analysis of the Mandarin and Cantonese tone systems with reference to multimodal learning, the authors recommend that teachers and curriculum developers should be more sensitive to tone-melody relationships when selecting or creating children’s songs for pedagogical purposes to better support CSL literacy development. It is also important to raise the preschoolers’ tone awareness, particularly in Cantonese-medium CSL classrooms, given the distinct tonal features of the target variety. Copyright © 2023 The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.