With the widespread use of digital media and the Internet, adolescents are at an increasing risk of exposure to sexually explicit content online. Such exposure has several physical and mental health effects that have become a key concern for healthcare professionals. This article introduces common online sexual risks, such as being involuntarily exposed, sending or receiving sexually explicit messages, and accessing sex-themed websites or videos unsuitable for minors. In Taiwan, many adolescents are exposed to sexually explicit content online, with this often occurring during mid adolescence; however, adolescents’ subjective perception of the risks associated with such exposure is low. Furthermore, adolescents’ age, gender, and traits such as fun-seeking, lack of perseverance and self-control, novelty-seeking, and rapid decision-making are significant factors influencing the risk of exposure. In the current digital era, integrating early health assessments, personalized prevention strategies, and protective family education is essential for establishing a safe digital environment for adolescents.