The present research aimed to address two questions. First, is dating anxiety associated with sexual intimacy anxiety? Second, do young people who report harmful sexual behaviour, as an offence or harmful dating behaviour, have higher levels of dating and sexual intimacy anxiety than young people who report no harm, non-sexual harm or sexual and non-sexual harm (generalists)? The Dating Anxiety Scale for Adolescents (DAS-A) was used to measure overall dating anxiety. Questions relating DAS-A sub-factors fear of negative evaluation and social distress - dating were amended to measure sexual intimacy anxiety. A scale to measure partnership anxiety and sexual behaviour anxiety were designed. Participants were 77 young people aged 13 to 18 years (M = 15.4, SD = 1.41). Forty-five (58%) of participants were female and 32 (42%) participants were male. Results found a strong, significant association between higher levels of dating anxiety and higher levels of sexual intimacy anxiety r(75) = .80, p < .001. Young people who reported a sexual offence had significantly higher sexual behaviour anxiety than non-sexual offence (M = 15.82, SD = 6.23, p = .005) and generalist offence groups (M = 21.77, SD = 6.53, p = .044). Despite no other significant differences, a pattern emerged that suggests young people who report harmful sexual or generalist dating behaviour may have higher dating and sexual intimacy anxieties. Furthermore, young people who report harmful dating behaviour may have higher anxieties than young people who report an offence. The implications of the findings for future harmful sexual behaviour and harmful dating behaviour research and practice are discussed.