As various contextual and individual difference factors determine how and when mindsets may influence learning outcomes, burgeoning L2 research has recently addressed the role of growth language mindset (GLM) in different learning outcomes such as L2 Willingness to Communicate (WTC). Since little is known about the underlying mechanism through which GLM may contribute to WTC, a highly desirable goal of L2 education and an important criterion for assessing its efficiency and success, the present study addresses this gap by investigating the possible mediating and moderating roles of linguistic risk taking and L2 learning experience, respectively. The participants were 392 Iranian L2 students chosen by multi-stage cluster sampling. Findings showed that GLM predicted WTC directly and positively, and their association was mediated and moderated by linguistic risk taking (an important affective factor) and L2 learning experience (an essential motivational factor), respectively. Suggestions for future studies and implications for promoting learners' GLM, linguistic risk taking, and L2 learning experience are presented.