The present study explores cross linguistic influence (CLI) on L3 Korean acquisition in Hong Kong higher education through analyzing learner’s particle errors in composition, particularly identifying the specific source of CLI –L1 (Cantonese/Chinese) or/and L2(English) in comparative linguistic perspective. A hybrid research approach is designed. Respondent’s particle errors in text assignment data and survey data are analyzed in descriptive and statistical approach correspondingly. In this thesis, majorities of findings regarding EA of particles are consistent with literature and there are also evidences of CLI on morphology stated in the literature such as inter-language grammars in word-order and semantic equivalence in different syntactic categories between source and target languages have been found in our data. It is argued positive transfer of morphology is possible if the semantic and syntactic function of morphemes between source languages and target language are identical or very similar and concluded that analysis of morpho-syntax would be crucial to identify CLI on Korean particle acquisition. Some of the important findings about the negative relationship between proficiency in source languages and CLI on Korean particle acquisition have been pinpointed. Significantly, the different roles of proficiency in L1 Chinese and L2 English are assumed as factors indicating learner’s error pattern and particle error rates respectively. The final part of the thesis is to apply theory into pedagogy. It is hoped that a tailor-made pedagogy, teaching L3 Korean in Hong Kong higher education where L2 English is teaching medium, will be achieved with the better understandings of learner’ particle errors and their causes. Certain issues of causes of particle errors except CLI are also outlined for further research in this area. / published_or_final_version / Linguistics / Master / Master of Arts