<p>In foreign/second language (L2) education, individual difference factors such as motivation, anxiety, and mindset play important roles in influencing willingness to communicate in L2 (L2WTC). However, there is a gap in the understanding of how the two components of L2 motivational self system—ideal L2 self and ought-to L2 self—affect L2WTC among Chinese middle school students. Moreover, the roles of communication anxiety and growth language mindset as mediators in these relationships have not been fully explored. Hence, this study aimed to explore the relationships between ideal L2 self, ought-to L2 self, communication anxiety, growth language mindset, and L2WTC. Data were collected from 847 students across four Chinese middle schools and analyzed using structural equation modeling (SEM). The results revealed that ideal L2 self and ought-to L2 self were directly and positively associated with L2WTC, while communication anxiety and growth language mindset were directly and negatively related to L2WTC. Additionally, ideal L2 self was found to positively predict communication anxiety, whereas ought-to L2 self negatively influenced it. Furthermore, both ideal L2 self and ought-to L2 self positively predicted growth language mindset. Communication anxiety and growth language mindset mediated the relationships between ideal L2 self and L2WTC, and between ought-to L2 self and L2WTC. Notably, three mediating paths demonstrated suppression effects. The findings of this study carry pedagogical implications for the field of L2 teaching and learning.</p>