Nutritional deficiencies among children and mothers in lower-income households in Sri Lanka continue to be a major obstacle to the country's social and economic development. This study investigates the factors affecting dietary caloric adequacy in Sri Lanka, paying special attention to maternal income. An econometric analysis was performed using a household data set collected from a sample of 183 low-income households in the urban, rural, and estate sectors. The results showed that on average, mothers and children in the sample did not consume adequate levels of calories according to the recommendations of the Medical Research Institute of Sri Lanka. The mother's income and educational status, the number of children and adults in the family, and the ages, sexes, and birth orders of the children significantly influenced household and individual caloric adequacy. Specifically, the mother's income had a significant positive effect on the total caloric intake (CI) and caloric adequacy ratio (CAR) of the household, mother, and children and a significant negative effect on the relative caloric allocation (RCA) of the children. The results imply that when maternal employment generates extra income, the CIs of all individuals increase, yet the allocation of calories to the children of the household is reduced. Thus, provision of employment opportunities for mothers, along with adequate child-care facilities and nutritional educational programs, is a possible strategy to improve caloric adequacy among low-income households in Sri Lanka.