Introduction: Climate change is a significant global health threat with disproportionate impacts across the Global South and among marginalized populations. Migrants and refugees experience multiple intersecting vulnerabilities including conflict, poverty and limited access to healthcare that may increase vulnerability to climate-related health impacts. This study aimed to explore perceptions of climate change and its impacts on mental health among migrant communities on the Thailand-Myanmar border. Methods: We conducted an exploratory qualitative study using focus group discussions (FGDs). Participants were rural migrant populations including pregnant women, adolescents, agricultural workers and healthcare workers living in Tak Province, Thailand. FGDs were audio-recorded, translated and analyzed thematically. Results: A total of 58 participants took part across eight FGDs. Participants' narratives centered around stressors they faced on account of their precarious legal status, financial insecurity and conflict-related trauma. Climate change was rarely raised spontaneously. Following direct prompts about climate change, participants described increasing exposure to extreme heat, flooding and environmental degradation which disrupted livelihoods and exacerbated existing hardship. The multiple stressors participants described interconnected to form a complex web of challenges. Discussion: In this conflict-affected, resource-constrained setting, climate change was rarely raised spontaneously as a life stressor. Against a backdrop of acute legal and economic stressors, climate-related distress may not be perceived as the most pressing concern. However, climate change may act as an indirect stressor through its impacts on livelihoods and exacerbation of structural precarity. Addressing the inter-related challenges of climate change, displacement, poverty and mental health requires integrative, climate-sensitive and migrant-inclusive health policies and care.