Abstract According to the literatures on attachment theory and depression, a number of researchers have provided empirical evidence to support the idea that family factors, especially parental attachment may contribute to depression. But until now, there is little research to explore the relationship between adolescent parental attachment and psychological suzhi, there is no research to explore the effect of psychological suzhi on the relationship between parental attachment and depression. Wang & Zhang (2012) presented the relationship model between psychological suzhi and mental health, and thought that psychological suzhi is developed during the interaction of social and cultural environment and hereditary and physiological basis, and it plays a crucial moderating or mediating role in the occurrence and development of illness, to be specific, it is reflected by that: the external protective or risk factors of mental problems act through psychological suzhi (internal). Based on the relationship model between psychological suzhi and mental health and attachment theory, this study presents a unique perspective on the underlying mechanisms of parental attachment in depression by focusing on the possible mediating roles of psychological suzhi. Using the cluster random sampling method, a total of 1482 students(689 middle school students, 793 high school students; 737 boys, 745girls) from 7-12 grades were surveyed. They were from 10 schools of 6 big areas in China. Participants completed paper-and-pencil version of the questionnaires of the Inventory of Parent Attachment (trust, communication and alienation to father and mother), Adolescent’s Psychological Suzhi Questionnaire(simplified version, including cognition quality, personality quality and adaptability) and Center for Epidemiologic Studies Depression Scale. Participants were informed about the voluntary and secrecy nature of the study. In this study, the hypothetical model was estimated using the maximum likelihood method (ML) and the bootstrap method in the Mplus program(version 7.0). In addition, as recommended by Wu & Wen (2011), the item parceling strategies (factorial algorithm) were adopted in the current study to solve the problem that a single latent variable contains too many observation indexes. Because independent samples t tests of gender and learning stage differences revealed that significant differences between boys and girls, between middle school students and high school students on study variables emerged, the variables gender and learning stage were controlled in the subsequent mediation modeling analyses. Analysis of the mediation model showed a good fit to the data (?2 = 520.057, df = 60, RMSEA = .072, CFI = .957, TLI = .936, SRMR = .046), and revealed that: (1) Adolescent parental attachment significantly positively predicted psychological suzhi. (2) The relationship between adolescent parental attachment and depression was mediated by psychological suzhi. Specifically, Psychological suzhi played a partial mediating role in father attachment and depression(effect size = 74.148%), a full mediating role in mother attachment and depression(effect size = 76.303%). (3) As recommended by Fang et al. (2014), the current study added some auxiliary (phantom) variables into the mediation model to examine the difference of mediation effects on father attachment and mother attachment. Results revealed that the influence of father attachment on depression was bigger than that of mother attachment. These results supported our theoretical hypotheses that psychological suzhi mediated the relationship between parental attachment and depression. To our knowledge, this is the first study of its kind, and it expands upon the growing body of research related to the relationship between parental attachment and depression by understanding the mechanisms leading to parental attachment individuals’ higher psychological suzhi. These findings have theoretical and applicative values for preventing and reducing depression.