Abstract The contrasting differences that exist in the English and Cantonese phonological systems result in divergent articulatory production between them. This article aims to investigate the negative transfer of Cantonese EFL learners in acquiring English consonant clusters and the constraint rankings of Cantonese and English syllable systems by comparing syllable structures and analyzing experimental statistics. The objective is to elucidate the reasons behind their negative transfer in English syllable acquisition. The research results demonstrated that Cantonese EFL learners found it easier to acquire consonant clusters in the onset position compared to the coda position. Additionally, an increase in consonants in the coda position posed greater difficulties for Cantonese EFL learners. The results also indicated that participants encountered the most problems with deletion, followed by substitution and epenthesis. The OT analysis reveals that the different rankings of faithfulness and markedness constraints in Cantonese and English led to transfer errors.