Despite that overall health indicators are on track to achieve the 2015 Millennium Development Goals, malnutrition continues to be a serious health concern in Sri Lanka. More than 20 per cent five under-five year olds are underweight, and 16 per cent of reproductive aged women were malnourished in the country. Apart from this overall picture, the country's Estate sector was worst affected in poor nutrition. For instance, about 30 per cent of children under the age of five are underweight, nearly 1 in 3 babies have low birth weight, and one-third of women of reproductive age are malnourished. It is recognized that, improved health care alone cannot improve all health outcomes. This is because there are deep rooted socio-economic factors affecting health. Thus, this study looks beyond health and explores the socio-economic determinants of child and maternal malnutrition in the Estate sector. Study findings contribute to policies on priority areas needing to be addressed in breaking the vicious cycle of malnutrition in the estate sector, in achieving overall goals of the country. Findings of this study revealed that unique causes such as, intake of imbalanced diet, household high alcohol and tobacco consumption, substantially contributed to child and maternal malnutrition in the estate sector. The study also revealed that low birth weight was a major cause of malnutrition. The author recommends that counselling programmes should be initiated for youth that promote positive health practices and curb negative ones like alcoholism and tobacco use.