The Northern Mountainous Region of Vietnam, home to diverse ethnic minority communities, is increasingly vulnerable to climate change, particularly in the agriculture sector. Smallholder farmers face mounting challenges due to shifting temperature and rainfall patterns. This study examines how smallholder farmers in Thai Nguyen and Son La provinces perceive climate change and the factors shaping their adoption of Nature-Based Solutions (NbS). Using a mixed-methods approach, including household surveys, semi-structured interviews and focus group discussions, farmers were found to recognise climate variability as a major driver of declining crop productivity and increased soil degradation. Despite awareness of the potential benefits of NbS, adoption remains limited due to financial constraints, insufficient technical knowledge and inadequate institutional support. However, findings highlight the value of integrating Indigenous knowledge and community-based initiatives into climate adaptation strategies. Context-specific policies, enhanced capacity building efforts and institutional mechanisms are recommended to promote the scaling up of NbS and strengthen the climate resilience of smallholder farming systems in Vietnam.