The use of peer assessment has been investigated for decades. However, the results of different studies are mixed. In this study, the implementation of peer assessment was attempted to assess students' reading aloud and oral presentation in two higher diploma/associate degree English language courses in Hong Kong. Students' opinions towards the implementation were obtained from the online questionnaire and follow-up interviews. In the end, 163 students from the two courses completed the questionnaire and 11 of them were involved in the interviews voluntarily. Apart from focusing on students' perceptions of peer assessment, the effects of the use of an online platform for peer assessment were explored. The results showed that more than half of the students were positive towards peer assessment because of their perceived benefits such as consolidating subject knowledge, engaging critical thinking and encouraging active student involvement in the assessment process. Regarding peer feedback, a few participants expressed that they were not confident in their abilities and English levels. Also, the majority of students interviewed commented negatively about the quality of their peers' feedback. Based on the findings, some implications for education and future studies were drawn.