This study analyzed the psychometric properties of scores on the Slovene version of the Questionnaire about Interpersonal Difficulties for Adolescents (QIDA) in a sample of 1,334 adolescents (44% boys), ranging in age from 12 to 18 years (M = 15.61). Confirmatory factor analyses replicated the correlated five-factor structure of the QIDA: Assertiveness, Heterosexual Relationships, Public Speaking, Family Relationships, and Close Friendships. Internal consistency and test-retest reliability were reasonable. Correlations of scores on the QIDA with scores of neuroticism, low extraversion, and low openness, as measured by the Inventory of Child/Adolescent Individual Differences, and scores of fear of negative evaluation, and tension and inhibition in social contacts, as measured by the Social Anxiety Scale for Adolescents were found, revealing differential links with QIDA subscale scores. Girls reported more difficulties than boys. Age differences showed a small but significant decrease in QIDA total score over adolescence.