The scale of global food insecurity is escalating because of conflicts, climate crisis and economic shocks and it is a multidimensional problem in south Asian countries. The objective of this study is to examine the long-term and short-term relationships between climate and non-climate factors and food security in South Asian countries. We analyzed the relationships between food security and other factors using panel ARDL model for the period 2001-2022 by computing mean group, pooled mean group and dynamic fixed effect. The dependent variable considered in study is prevalence of undernourishment which is modeled against independent variables like food production index, land area under cereal cultivation, GDP per capita, population, inflation, rainfall, temperature, cereal import dependency. Our results showed that, for an increase of land area under cereals and GDP per capita improve the food security by 0.03 % and 0.003 % respectively and if population increase pushes down the food security by 4.34 % for every unit increase. Climate variables like rainfall, temperature and cereal imports doesn’t drive the food security in long run. The country specific effects are heterogeneous among South Asian countries as food security is being determined by climate factors in Afghanistan and Nepal and by non-climate factors in India. The study concluded that food insecurity can be reduced by improving GDP per capita, food production and by controlling population expansion. Since, the long run relationship is more significant that short run relationship it signifies the importance of long-term developmental policies in affirming food security condition of South Asia.