Purpose:Social networks provide convenient communication and connection among people, and they have become essential in college students' lives. However, problems also come along with increasing concern about trust and privacy issues. This research attempts to investigate the trust and privacy perceptions of university students when using social networks for learning purposes.Design/methodology/approach:This paper investigated the differences in trust and privacy perceptions between undergraduate (UG) and postgraduate (PG) students through an online survey with 96 subjects in Hong Kong. The authors used the Mann–Whitney U test to compare the differences between the responses provided by UG and PG subjects.Findings:The authors found that both PG and UG students were generally satisfied with the use of social networking sites (SNSs) for learning. However, PG subjects used SNSs more for learning and were more willing to exchange with classmates than UG and PG perceived higher value of SNSs than UG students. The authors also found a relative lack of privacy awareness of UG students.Practical implicationsBased on the study’s findings, the authors made some recommendations about the application of SNSs for learning purposes. The authors also suggest universities provide more guidance and training to students on the privacy issues of SNSs.Originality/value:Even though some previous studies have focused on studying privacy and trust issues on SNSs, studies that aim at university students in the context of Asia–Pacific are rather limited, especially university students' own trust and privacy perceptions on using SNSs for learning purposes. Copyright © 2021 Emerald Group Publishing Limited