<p>Artificial intelligence (AI) is increasingly reshaping second language (L2) learning by providing learners with more interactive, flexible, and personalized forms of support. Yet how learners’ perceptions of AI affordances develop into attitudes toward AI-assisted L2 learning remains insufficiently understood, particularly in relation to the psychological processes involved. To address this gap, the present study examined the relationships among perceived AI affordances, autonomous learning, grit, technology trust, and learner attitudes. Questionnaire data from 623 Chinese EFL learners were analyzed using partial least squares structural equation modeling (PLS-SEM). The results showed that perceived interactivity, convenience, and personalization were positively associated with learner attitudes, whereas social presence had no significant direct effect. Convenience and social presence were indirectly related to attitudes through the sequential pathway of autonomous learning and grit, while personalization also exerted an indirect effect through grit. Technology trust strengthened the relationship between autonomous learning and grit, but did not moderate the link between autonomous learning and attitudes. These findings provide insight into the relationship between perceived AI affordances and learners’ attitudes toward AI-assisted L2 learning, highlighting the roles of autonomy, grit, and trust.</p>