Language-related academic emotions, especially foreign language anxiety (FLA) and foreign language enjoyment (FLE) have been widely explored, and foreign language boredom (FLB) has gradually attracted more and more attention. Previous research has examined the relationship between language-related academic emotions (FLE, FLA, and FLB) and language performance, but the findings have been inconsistent. By synthesizing the existing literature, we aim to provide a clearer understanding of the relationship between these emotions and language performance. Thirty-nine studies with 130 independent samples from 9 countries and 91,405 participants were included in our meta-analysis. The results show that FLE has a positive impact on foreign language achievement(r=0.339), while FLA and FLB have negative impacts (r=-0.259 and r=-0.288, respectively). FLE emerges as the most significant factor affecting foreign language achievement. Subgroup analyses and meta-regression analysis were performed to examine potential moderators, revealing that age and linguistic differences do not have a significant impact on this relationship, but education level and the type of achievement measure play a crucial role in mediating the effects of FLE and FLA on language achievement. The findings provide evidence for the effectiveness of language-related emotions on language achievement and have important implications for language learning research and practice.