Introduction: Mentalization, which is defined as the capacity to understand the mental states of oneself and others, can be an important factor in social anxiety disorder. This study aimed to investigate the causal model of insecure attachment style and traumatic experiences mediated by mindfulness on the mentalization of people with social anxiety. Materials and Method: The present study is quantitative correlation and structural equations. The statistical population of the study included all students of Payame Noor University in Aleshtar in 1399. 232 students who scored above 40 in the Conover Social Anxiety Questionnaire were selected as the sample. Data collection tools included: Connor Social Anxiety Questionnaire, Dimitrievich mentalization, Hazen Attachment Style, Mohammadkhani Traumatic Experiences, and Freiburg Mindfulness. Data were analyzed using structural equations using AMOS software. Results: The results showed that the hypothetical model of the research has a good fit with the data. Insecure attachment style and traumatic experiences had a significant negative relationship with mentalization. Mindfulness was able to significantly mediate the relationship between insecure attachment and mentalization, but mindfulness did not play a significant mediating role in the relationship between traumatic experiences and mentalization. Conclusion: The results of this study indicate that insecure attachment style, directly and indirectly, affects mentalization through mindfulness and traumatic experiences can only directly affect mentalization. Paying attention to these variables can be effective in solving mental problems and improving them. Extended bstract Introduction Mentalization is a multidimensional structure and is considered as the capacity and ability of human beings to interpret and understand the psychic states (thoughts, feelings, intentions, desires, and goals) of themselves and others and to identify the psychic states, which are the basis of human behavior helps. Since the function of social and interpersonal successful affiliate encoding and argued exact beliefs, intentions, thoughts, desires, and emotions in oneself and others, people with social anxiety disorder due to a deficiency in the mental ability of injuries and interpersonal problems many they experience. Based on this, it seems that defects in mentalization play an important role in conceptualizing, creating, and perpetuating social anxiety disorder. Recent studies have shown an association between attachment style, early traumatic experiences, and mindfulness with mentalization. Methods The present study was quantitative correlation and structural equation modeling. The statistical population of the present study included all students of Payame Noor University of Aleshtar city in Lorestan province who were studying in this university in 1399-1400. The sample size according to the proposed views to be 15 people for each measured variable, also Klein (2010) claims that the minimum sample size of 200 people can be defensible since in this study There were 12 variables measured, 180 subjects were acceptable. However, in this study, 232 people were selected as the sample. After completing the Connor Social Anxiety Questionnaire and receiving a score above 40, students were selected as the sample of the study. In the present study, 232 people were considered as a sample. Hazen and Schiver Attachment Style Questionnaire (1985), Traumatic Experiences of Mohammad Khani et al. (2003), Freiburg Mindfulness Questionnaire (2006), Dimitrievich et al. Mentalization Questionnaire (2017). Criteria for admission to the study Having informed consent to participate in the study was a score above 40 in the Conover Social Anxiety Questionnaire, and exclusion criteria include not having inclusion criteria and incomplete completion of the questionnaire. The structural equation method was used to analyze the data and study the model. In this study, the variables of attachment style and traumatic childhood experiences were studied as exogenous variables, mindfulness variable as mediating variable, and subjectivity variable as an endogenous variable. Data were analyzed using spss-24 and amos-24 software. Findings The direct effect coefficient of insecure attachment style on mentalization was-0. 286, which was negative and significant at the level of 0. 014. In the field of a direct causal relationship, traumatic experiences on mentalization have a direct impact factor of-0. 634, which was negative and significant at the level of 0. 001. Also, the coefficient of the direct effect of mindfulness on mentalization is equal to 0. 211, which is a positive and significant relationship. The bootstrap test has been used to investigate the significant role of mindfulness as a mediating variable between insecure attachment style, traumatic experiences, and mentalization. Based on the bootstrap test, upper and lower limit the indirect causal relationship between insecure attachment style and mentalization with the mediating role of mindfulness was-0. 034 and-0. 269, respectively, and since the number 0 is between the upper and lower limit It can not be concluded that there is a significant indirect relationship between these two variables with the mediating role of mindfulness. About traumatic experiences with high and low-level mentalization, it is equal to 0. 045 and-0. 07, respectively, and since the number 0 is between these two values, it can be concluded that mindfulness is related to the style of traumatic experiences. Generation and mentalization did not play a significant mediating role. According to the model fit indices of chi-square on the degree of freedom 2. 13 which is within an acceptable fitting distance, the values of adaptive fit indices GFI, CFI, IF, NFI, and AGFI have been obtained to a very desirable level, which indicates a fit. The data is with the original model, also for the RSMEA index, this value is equal to 0. 070, which means the model fits and its final approval. In general, the values obtained in the present study are in the desired range compared to the desired values for these indicators, so it can be concluded that the model has a good fit. aimed to investigate the causal model of insecure attachment style and traumatic experiences mediated by mindfulness on the mentalization of people with social anxiety. Discussion and Conclusion The perpuse of this study to investigate the causal model of insecure attachment style and traumatic experiences mediated by mindfulness on the mentalization of people with social anxiety. According to the fitted model, insecure attachment style had a direct and indirect effect on mentalization through mindfulness mediation. on the other hand, the direct and significant effect of traumatic experiences on mentalization was revealed, but mindfulness could not be indirectly effective in the relationship between traumatic experiences and mentalization. The limitations of this study are that the research method was correlational studies, so it is not possible to deduce a definite causal relationship in this study. On the other hand, the study participants were students, which makes Generalization of the results of the necessary consideration should be considered, since the component of mentalization has been less studied internally, researchers can study and study mentalization on other societies and its relationship with other variables, and Specialists and therapists can use the findings of this study in relation to people with social anxiety. Ethical Considerations Compliance with ethical guidelines All subjects answered the questionnaires with complete satisfaction Funding No funding. Authors' contributions Design and conceptualization: safari mousavi, Sadeghi and sepahvandi Methodology and data analysis: safari mousavi, Sadeghi and sepahvandi Supervision and final writing: sadeghi Conflicts of interest The authors declared no conflict of interest.