ENThe study explored the relationship between young adults’ thinking styles, parental marriage relationship and implicit theories of relationships. 394 university students from 6 Lithuanian universities filled out Thinking Styles Inventory (TSI-R2) (Sternberg, Wagner, & Zhang, 2007), Implicit Theories of Relationship Scale (ITR) (Knee, et al., 2003), and a Parents’ Marriage Characteristics Measure (Hall, 2003). The study found predictors of growth and destiny implicit theories of relationships among thinking styles and parental marriage characteristics. Parental marriage characteristics had lower-than-expected predictive power as well as lower predictive power than thinking styles. The results provide insight into the development of implicit theories of relationships within the Social-Cognitive and Mental Self-Government frameworks as well as implications for research, counseling, and education on relationships.