The prevalence of mental disorders among young adults in Indonesia has increased, indicating the importance of improving mental health literacy among them. This study aimed to determine the social determinants and mental health literacy among first year undergraduate students of Universitas Hasanuddin, South Sulawesi, Indonesia. Data for this study came from the Indonesia Health Literacy Study 2019, a cross-sectional online survey of undergraduate students from four public universities in four provinces of Indonesia. Mental health literacy was measured using the Mental Health Literacy Scale (MHLS) which had been adapted into Indonesia context. The results showed that respondents had relatively low mental health literacy (M=59,60 on a scale of 0-100). Bivariate analysis showed that gender, relationship status, and scientific clusters were associated with MHLS. Multivariate analysis showed that mental health literacy was lower among male students, students who refused to reveal their ethnic identities, and students of science-tech cluster. Interventions through mental health education and mental health call center are recommended to improve mental health literacy, especially among these undergraduate students of Universitas Hasanuddin.