<p>This study employs data from the China Labor Dynamics Survey to examine the impact of dialect distance between migrants' place of origin and destination on their subjective well-being in China, as well as the underlying mechanisms involved. The sample comprises 1674 migrants between the ages of 18 and 70, with a mean age of 41.30 and a standard deviation of 11.26. Among the total sample, 52% are male. The results show that the dialect distance between migrants' origin and destination has a negative impact on their subjective well-being, controlling for a variety of sociodemographic characteristics. The mechanism analysis demonstrates that the cultural identity effect of dialect is a pivotal mechanism through which dialect distance affects the subjective well-being of migrants. As migrants arrive at an earlier age, reside for longer periods, and become more proficient in Mandarin, the national common language of China, the impact of dialect distance on their subjective well-being is reduced. The findings of this study elucidate the relationship between linguistic distance and the subjective well-being of migrants and provide novel evidence for the role of language in their social integration.</p>