In Europe, 82% of minors use a social network (SN). Although SNs offer opportunities for social interaction, they also involve some risks, such as online sexual victimization (OSV). As many as 39% of teenagers are estimated to be at risk of OSV. The literature suggests that risky online behaviors, such as sexting, indiscriminate expansion of SNs, and intimate and face-to-face relationships with strangers met online, can increase the risk of OSV among adolescents. The aim of the study was to investigate the prevalence of OSV and related risk factors in a sample of early adolescents. A cross-sectional study was conducted based on 310 Italian adolescents (12–14 years old) who completed the Juvenile Online Victimization Questionnaire (JOV-Q). Sixty percent of the sample reported at least one form of OSV, with males more at risk than females. Age, gender, and online risk behaviors are predictors of different kinds of OSV. In the whole sample, the most frequent kind of OSV was unwanted exposure to sexual content, followed by sexual pressure, online grooming, and sexual coercion. Sexting and indiscriminate expansion of one’s network increase the likelihood of having been the target of at least 1 OSV in the past year. Early adolescents can face a higher risk of OSV than adolescents, based on known percentages. The study of the prevalence and risk factors in this age group therefore deserves specific attention in order to design programs to prevent and combat OSV.