Hong Kong's universities have been attracting non-local students to diversify the overall student mix and enhance internationalism in higher education. Mainland Chinese students have become the largest non-local student source in this Western-style higher education sector. The diversity of student body together with the promotion of multicultural experience has created major concerns about provision of high quality learning and teaching. Studies show there have been potential peer interaction obstacles between local and mainland students due to different social, cultural and educational backgrounds. However, research on the role of teachers in facilitating peer interaction is limited. This paper reports an investigation on how teaching strategies used in the English Department had an impact on enhancing peer interactions in the university classroom context. Classroom observation containing textual descriptions and numeric interpretations was used. Solutions were recommended to improve the multicultural learning environment in Hong Kong and other universities with diverse student cohorts.