Background: During the COVID-19 pandemic, the number of people suffering from psychological disorders has increased all over the world. Objectives: The present study aimed to investigate the relationship of mental health and resilience with Posttraumatic Growth (PTG) through mediating of defensive styles in the COVID-19 survivors. Materials & Methods: This was a descriptive cross-sectional study using Structural Equation Modeling (SEM). The research population included all COVID-19 recovered patients in Gorgan, Iran. Using convenience sampling method, 300 patients who recovered from COVID-19 were selected. The research instruments included the Posttraumatic Growth Inventory, Connor- Davidson Resilience Scale, the General Health Questionnaire, and Defense Style Questionnaire. The participants were given questionnaires online. Results: The results of SEM suggested that the proposed model fits the data. The direct paths from PTG, mental health, and resilience to the developed defensive styles were positive and significant (P<0.01). In addition, the relationship between mental health and resilience with PTG was positive and significant (P<0.01). The relationship between PTG, mental health, and resilience with the immature and neurotic defensive styles was negative and significant (P<0.01). Conclusion: The findings revealed that mental health, resilience, and developed defensive styles had a tremendous impact on the increase of PTG in COVID-19 patients. Accordingly, they can be used to reduce the psychological problems caused by the COVID-19 pandemic.