Introduction: Masculinity and femininity constitute the gender role construct into the general concept of sexual identity. Aim: To investigate the relationships of attachment style, sexual orientation and biological sex with the gender role. Methods: A convenience sample of 344 subjects (females ¼ 207; males ¼ 137) was recruited. Main Outcome Measures: The Attachment Style Questionnaire (ASQ), the Kinsey Scale, and the Bem Sex Role Inventory assessed, respectively, attachment styles, sexual orientation, and masculinity/femininity was administered. Results: Regression analysis revealed that the confidence scale of the ASQ (secure attachment) and relationship as secondary scale of ASQ (insecure/dismissing attachment) have a predictive role toward a higher score of masculinity (b ¼ 0.201; P ¼ .000 and b ¼ 0.208; P ¼ .000, respectively), whereas the need of approval scale of the ASQ (insecure/fearful-preoccupied attachment) shows a reverse association on it (b ¼ À0.228; P ¼ .001). Moreover, to be a male is predictive for masculinity (b ¼ 0.196; P ¼ .000). Also, femininity is predicted by the confidence (b ¼ 0.173; P ¼ .002) and the need of approval (b ¼ 0.151; P ¼ .03) scales of ASQ. Instead, the relationship as secondary scale of ASQ is negatively related to femininity (b ¼ À0.198; P ¼ .0001). No association between non-heterosexual orientation and gender role was found. Clinical Implications: A better knowledge of links between relational patterns and gender roles for assessment and anamnesis phases in sexual medicine. Strengths & Limitations: This is the first study considering sexual orientation and biological sex in the relationship between attachment styles and gender role. The main limitation is the use of self-reported psychometric tests. Conclusion: Our data indicate that a secure attachment is related to both masculinity and femininity. On the contrary, different and reverse aspects of insecure attachment style characterize masculinity and femininity. Masculinity is mostly linked to insecure/dismissing attachment, whereas femininity is linked to insecure/fearfulpreoccupied attachment. Moreover, although being male is a further element in support of masculinity, sexual orientation is not associated with gender role.