With the development of the Internet, Internet vigilantism (netilantism) has emerged as a new phenomenon in recent years. Although there are several qualitative studies explaining netilantism, there is little empirical research on public perceptions of netilantism. This article aims to outline Hong Kong university students’ general perception of netilantism and investigate the differences between different roles in netilantism. By using empowerment theory as the theoretical framework, we will investigate whether Internet vigilantes (netilantes) (a) perceive the criminal justice system as effective, (b) possess high levels of self-efficacy in the cyber world, and (c) tend to believe netilantism can achieve social justice. Findings support the proposition that human flesh search engine is an empowerment tool for the netilante enabling him or her to achieve his goal of social justice. Different roles in netilantism (i.e., bystander, netilante, victim, and none of the above roles) have different perceptions of netilantism and the criminal justice system. The results will be explained by studying two representative cases of netilantism—the "Government Official Molestation" case and the "Cat Abuse in Shun Tin Village" case from China and Hong Kong, respectively.