This study examines farmers' interest in implementing Climate Smart Agriculture (CSA) in Northern Sumatra. Climate change is one of the environmental factors that can have a negative impact on lowland rice productivity due to several abiotic factors such as rainfall, drought, flooding, temperature and solar radiation that affect rice production. The aim of this study is to examine the level of interest of lowland rice farmers in implementing CSA and to examine the factors that influence the interest of lowland rice farmers in implementing CSA in Northern Sumatra. This type of research is descriptive quantitative by testing 5 variables X (education, farming experience, characteristics of innovation, the role of government, and role extension) and Variable Y (Farmers interest). Respondents were 44 farmers and the sampling technique was Non Probability Random Sampling. Data were analyzed by Multiple Linear Regression. The result of the analysis is that the influence of variable X simultaneously is 62.3% on variable Y (farmers' interest). The influences of partial variables are X1 (14.7%), X2 (33.5%), X3 (40.6%), X4 (35.5%) and X5 (2.7%). The level of interest of farmers to the application of CSA in increasing rice production in the sub-district is 76.3% or in high category.