Aim: This research was carried out with the purpose of investigating The Mediating Role of Interpersonal needs and Parent-Adolescent Conflict in the Relationship Between Parenting Styles and Basic Psychological Needs with Non-Suicidal Self-Injury and Suicidal Ideation. Method: Research statistical population were the 224, 400 male and female high school students in Tehran in year 1398-1399. Among them 420 students were selected via sampling cluster random method. The research instruments consisted of: Beck scale for suicide ideation (Beck, Kovacs & Weissman, 1979), Self-harm inventory (Sansone, Wiederman & Sansone, 1998), Basic needs satisfaction in general scale (Gagne, 2003), Parents as social context questionnaire (Skinner, Snyder & jonson, 2005), Conflict behavior questionnaire (Robin & Foster, 1989) and Interpersonal needs questionnaire (Van orden, Cukrowicz, Witte & joiner, 2012), Result: Data were analyzed using Pearson correlation coefficient and structural equations. The results of structural equations showed that parenting styles and basic psychological needs have a significant indirect effect on non-suicidal self-injury and suicidal ideation through thwarted belongingness, perceived burdensomeness and parent-adolescent conflict. Conclusion: Based on the research results, it can be found that the reduction of thwarted belongingness, perceived burdensomeness and parent-adolescent conflict in adolescents can play an effective role in reducing non-suicidal selfinjury and suicidal ideation.