The main research objective of this study was seeking the predictive role of closeness to parents, attachment, identity style, identity commitment, type of relationship, and having children in intimacy among young women and men. Many studies indicate differences in the level of engagement, communication, and satisfaction in relationships. The study group comprised 227 people, including 114 women (M = 29.99; SD = 4.36), and 113 men (M = 30.00; SD = 4.33). A total of 40% of the subjects were married, and the remaining 60% subjects were in informal relationships; 101 people had children and the other individuals were childless. The following instruments were used: The Miller Social Intimacy Scale, questionnaires to assess closeness and attachment, and the Identity Style Inventory. The significance of the differences and the stepwise regression analysis were performed. The results of the study demonstrated a higher level of intimacy in a relationship with a partner among women than men. The nature of a relationship does not matter to the sense of intimacy. However, closeness to parents during childhood and adolescence, the model of interpersonal relations, and the identity style are predictors of intimacy in a relationship. The study results can be used in creating preventive and educational programs focused on family life and satisfied relationships.