Introduction <p>In an era of digitalization, online sexual harassment (OSH) has become a pervasive global issue, yet remains poorly understood. OSH refers to a spectrum of uninvited and unwelcome sexual behaviors—including sexual comments and solicitation—that take place on digital platforms. Using the lens of frames and framing ambiguity, this study explores the challenges faced by victims in identifying OSH and considers factors influencing their interpretations.</p> Methods <p>Data were collected through in-depth interviews conducted in Hong Kong between 2021 and 2024 with 41 victims of online sexual violence.</p> Results <p>Our analysis reveals that victims used frames inconsistently when interpreting their OSH experiences: some described their experiences as unrelated to sexual harassment (<i>out-of-frame</i>), shaped by factors such as inadequate sexuality education, a perceived hierarchy of sexually harassing behaviors, and the borderless and anonymous nature of cyberspace. Others misinterpreted their OSH encounters (misframed), often due to unclear boundaries between sexual interest and harassment, confusion about perpetrators’ motivations, and cultural norms in cyberspace. In most cases, victims eventually recognized OSH victimization after gaining new knowledge and conceptual clarity (<i>reframed</i>).</p> Conclusions <p>Our findings highlight the need to enhance young people’s understanding of sexual harassment in general, and OSH in particular, to enable timely and effective responses.</p> Policy Implications <p>This research calls for sexuality education reform by implementing a structured, digitally informed curriculum with mandated instructional hours, establishing a definition of OSH aligned with legal and scholarly definitions but also accessible to layman, and strengthening laws to address the distinctive challenges of OSH.</p>