The current study examined the relationships between borderline personality traits, mother-and-child image and internal objects in adolescence. Questionnaires were distributed to 253 university students. In total, data from 227 participants were analyzed after excluding incomplete responses. The results revealed that, even among those who established stable mother-child relationships in early childhood and for whom “good subjects” were internalized, there was only a positive correlation with “concerns about disgust” or “connection desire”. In addition, there was a positive correlation between “bad subjects” as “relationship breaks” and “non-permanent objects” as “concerns about aversion,” “isolation”, and “connection desire”. These findings suggest that some young people desire to be hated and have connections with others. However, when characteristics such as breaking a relationship or feeling a vague sense of isolation are added, interpersonal relationships were found to be unstable, representing more borderline personality traits. In addition, we conducted interviews with 12 university students and examined how mother-child relationships in early childhood and internal objects influenced current borderline personality traits. The results revealed that, even for young participants with a stable mother-to-child relationship, youth-related characteristics and previous interpersonal relationships could affect borderline personality traits.