The aim of this quantitative research was to examine the relationship between the characteristics of the primary family and the determinants of relationship quality. A non-experimental, correlational design was used. The characteristics of the primary family were viewed through the attachment to parents and the perception of the parental relationship, more precisely the conflict between parents in childhood. The quality of the relationship was determined through commitment, satisfaction, stability and attachment to the partner. The research was conducted through an online survey on a sample of 217 young adults aged 19-30 who are currently in a relationship or have experience of a relationship. The following instruments were used: Relationship Investment Model Scale, Relationship Stability Assessment Scale, Brennan's Inventory of Experience in Close Relationships - partner and family domain, and the Scale of Perception of the Quality of Parental Relationship in Childhood. The obtained results largely confirmed both, affirmatively set hypotheses. The results indicate the existence of a negative connection between attachment to parents and commitment to the relationship, satisfaction and stability of the relationship, and a positive connection between attachment to parents and attachment to the partner in the same dimensions of anxiety and avoidance. Regarding the second aspect of the primary family, the results established a negative association of the perception of parental conflict with the satisfaction and stability of the partner relationship, and a positive association with attachment to the partner. Only for the commitment to the relationship, no significant connection was found with the dimension of parental avoidance, nor with the perception of parental conflict in childhood. The obtained data are in accordance with the previous theoretical and empirical knowledge in this area. The results of this research emphasize the need for the work of experts primarily in the field of family, but also in the field of effective establishment and maintenance of quality partner relationships among young adults.