Similar to several agricultural economies, India is prone to erratic rainfall in some of its regions. Apart from scanty rainfall; heavy rains leading to unexpected floods is common in this country. These unexpected floods can create devastating impacts on food security of the people and their livelihoods. These impacts would be severe on the internally displaced people staying particularly in the tribal regions. The present paper is an attempt to study the impact of unexpected floods on food security and livelihoods of internally displaced people (IDPs) of Khammam region of Andhra Pradesh in India. A simple descriptive methodology including a binary logit model has been used to verify the impact on food security and livelihoods of IDP households in the study area, Bhadrachalam. The study reveals that the impact of floods could be seen across all the variables affecting livelihoods in all the families living in 21 settlements. Floods have caused extensive damage on the roads and bridges in the Bhadrachalam region virtually delinking the areas and rendering them impassable. The damaged infrastructure impacted negatively on the delivery of services such as health, agriculture and education in the area. The binary logit model estimated on the basis of survey data of 124 IDP households indicates that floods had a negative impact on food security by reducing the purchasing power, wage income, resulting in food shortages, increasing borrowing and altering the food habits and resulting in sickness among households. In view of these findings some policy interventions have been suggested.