This study examines gender differences in young adults’ privacy beliefs, their reactions to behavioral advertising, personal information-sharing behaviors, and privacy protection behaviors on social networks. This investigation uses a large-scale survey of college students based on a social networked sampling technique facilitated through a Facebook group. Results reveal several gender differences in these areas. Third-party data usage beyond the original purpose and behavioral advertising techniques are of concern to both genders but more to women. In addition, women engage in noticeably more proactive privacy protection behavior compared with a decade ago. The authors conclude with a discussion of implications for behavioral advertising.