Engagement and willingness to communicate (WTC) are crucial elements for second language (L2) learning. However, little is written about whether L2 learners demonstrate heterogeneous patterns of engagement and WTC in the classroom. This study aims to identify intraindividual differences in these two constructs and examine the roles of eight achievement emotions in predicting these profiles. To this end, 607 Chinese college L2 learners were recruited to complete three valid scales. Latent Profile Analysis (LPA) using Mplus 8.7 revealed a four-profile solution: high engagement-low engagement (C1: 26.85%), moderate engagement-moderate WTC (C2: 48.11%), moderate engagement-low WTC (C3: 14.83%), and low engagement-low WTC (C4: 10.21%). Multinomial logistic regression analyses revealed that negative achievement emotions did not predict these profiles, whereas positive ones did. Particularly, "enjoyment" was a positive predictor for all profiles, with a decreasing order of impact (C1 > C2 > C3 > C4). "Hope" did not differentiate between C1 and C2 but showed a decreasing influence on the subsequent profiles (C1 = C2 > C3 > C4). Lastly, "pride" was a significant predictor only for C4 (C1 = C2 = C3 > C4). This study also discusses the theoretical and pedagogical implications and suggests directions for future research.