Background Migration is a social determinant of health, as human mobility is associated with the health outcomes of those who move. Social sciences research on migration and health needs to transition from an individual approach to models that reveal how place, processes of racialization, and structural elements impact immigrant health. We aim to describe, from the key informant's perspective in depth, the case of intersectionality, racism, and gender and related perceived effects on Venezuelan migrants' mental health at two relevant Latin American borders. Methods The present study is a multisite observational cross-sectional qualitative project on two selected borders, the northern borders of Chile (Antofagasta, Iquique, Arica) and Ecuador (Tulc & aacute;n, Nueva Loja). In-depth semi-structured interviews with key informants were collected in (n = 30) Chile from May to December 2022 and in Ecuador (n = 30) from October to December 2022. 22 participants were men, and 38 were women, and in-depth interviews were analysed using an inductive thematic approach. Findings We found structural axes (i.e., socioeconomic, migration status, gender) of power that intersect in migrants' and refugees' conditions and experiences in their access to health and mental health care. Interpretation We proposed the notions of intersectionality and racism to deliberately connect complex and dynamic concepts relevant to migrant and refugee health research, such as the racism faced by historically racialized populations based on their phenotypes, social class, and/or nationality and socioeconomic and gender inequalities. Funding Deutsche Forschungsgemeinschaft-468252559. TRJ: ANID 11200486, Fondecyt Regular 1231102, ANILLO ATE230065, MILENIO-N degrees NCS2021_013. BC: ANID Fondecyt Regular 1201461. Copyright (c) 2025 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).