The purpose of this study was to estimate the minimum monthly food cost for the low income population. The food consumption data of 9,311 individuals from the 2001 Korean National Health and Nutrition Survey was used. The monthly food cost was calculated using the Consumer Food Price Database for the year 2001 provided by the Public Health Nutrition Laboratory, Seoul National University. The low income population (n = 1,310) was characterized as older age, lower income, smaller family size, lower education level, and lower energy intake as compared with the total population (n = 8,001). The estimated food cost showed that men in the low income population needed 15% more money for purchasing food to maintain the energy intake level at the average energy intake level of men in the total population. It was also estimated that women in the low income population needed 9% more money for purchasing food to maintain the energy intake level at the average energy intake level of women in the total population. There were differences in monthly food costs depending on the sex and age, and family size. The results of this study could be used as basic information to establish minimum food cost for the low income population in Korea.