Objectives : During the past two decades, food deprivation and hunger have been recognized to be not just the concerns of only underdeveloped or developing countries, but as problems for many affluent Western nations as well Many countries have made numerous efforts to define and measure the extent of these problems. Based on these efforts, the theory and practice of food security studies has significantly evolved during the last decades. Thus, this study aims to provide a comprehensive review of the concept and measurement of food security Methods and results : In this review, we introduce the definition and background of food security, we describe the impact of food insecurity on nutrition and health, we provide its measurements and operational instruments and we discuss its applications and implications. Some practical information for the use of the food security index in South Korea is also presented. Conclusions : Food security is an essential element in achieving a good nutritional and health status and it has an influence to reduce poverty The information about the current understanding of food security can help scientists, policy makers and program practitioners conduct research and maintain outreach programs that address the issues of poverty and the promotion of food security.