Tropical regions such as Southeast Asia are more vulnerable to food insecurity because climate change causes disruptions in the food supply chain. An extreme increase in the population exacerbates this condition. Southeast Asia also often experiences extreme weather, adversely affecting the farmers’ livelihood. Climate change that has occurred for decades has forced smallholder farmers to adapt. This study aims to identify the impact of climate change and adaptation strategies of smallholder farmers and other Southeast Asian stakeholders. The methods used in this study are bibliometric analysis and systematic literature review (SLR). The result explains that climate change significantly impacts the decline in agricultural productivity, food nutrition, environmental quality, and resource instability. Climate change has also contributed to the increase in poverty. The adaptation strategies at the upstream level include sustainable agricultural practices, agroforestry, circular economy, crop-livestock integration, forest recovery, environmentally-friendly technology, changes in sowing and planting dates, traditional water irrigation practices, and smart farming. At the downstream level, many rural farmers migrate to cities because they cannot continue farming. The government has implemented social protection and climate risk insurance schemes for farmer households at the downstream level.