Incremental intelligence plays an important role in self-regulating and enhancing writing performance among language learners. The present study aimed to investigate the relationship among variables of the incremental theory of intelligence, self-regulatory writing strategies, implicit theory of writing, and writing performance in EFL learners. To do so, 320 Iranian IELTS candidates were invited to participate in the study. Three questionnaires, namely incremental intelligence, self-regulatory writing strategy, and implicit theory of writing, were utilized. The participants included male and female IELTS candidates aged 19-27 years with a minimum band score of 6.5 in their writing skill. Furthermore, their educational qualifications included BA and MA degrees. The collected data were analyzed using SPSS and structural equation modeling (SEM). The correlation analysis showed that the incremental theory of intelligence had a significant relationship with self-regulatory writing strategy, implicit theory of writing, and writing performance. Moreover, the obtained results of SEM confirmed the findings of the correlational analysis, indicating statistically significant positive correlations among the variables of the study. The findings revealed that a growth-oriented mindset could affect students' use of four types of self-regulatory writing strategies. Self-regulatory writing strategies also played a pivotal role in guiding, stimulating, motivating, and sustaining learners' efforts, thus predicting writing performance. The results of this study can help EFL learners learn how to regulate and manage themselves in writing skills. Learners can assess the extent of their professionalism and endeavor to identify their weaknesses in the learning process.