This entry provides a comprehensive examination of factors influencing the mental health of Vietnamese migrants in Japan. In recent years, the Vietnamese population in Japan has rapidly increased, making the impact of labor conditions and socioeconomic factors on mental well-being more apparent. Technical interns face excessive working hours, restrictions on job mobility, and unfair treatment, all of which exacerbate their psychological stress. Additionally, economic hardships compound their mental health burdens. Limited proficiency in the Japanese language not only creates barriers to workplace communication but also hinders access to healthcare services, making it difficult to receive appropriate mental healthcare. Moreover, the deep-rooted cultural stigma surrounding mental illness creates a reluctance to seek psychiatric treatment, preventing individuals from obtaining the necessary support. The coronavirus disease pandemic and natural disasters have profoundly affected mental health worldwide. Social isolation due to infection control measures, financial hardships among international students and technical interns, and separation from family members increase the risk of anxiety and depression. Furthermore, the lack of disaster-related information in Vietnamese has heightened anxiety among migrants in the wake of the 2024 Noto Peninsula Earthquake and frequent seismic disasters. Conversely, religious support through Buddhist temples and cultural exchange activities within local communities have the potential to promote psychological stability and alleviate feelings of loneliness. To address these challenges, it is crucial to improve labor conditions, establish medical interpretation services, enhance information and communication technology-based mental health support, and promote policies that foster multicultural coexistence. Based on the findings of this entry, further empirical research is needed to develop comprehensive support measures to improve the mental health of Vietnamese migrants in Japan.