Background: Undernutrition coexisting with overweight or obesity in the same population is a growing global public health concern, especially for the internally displaced. Aim: To identify a double burden of malnutrition, comprising underweight and overweight/obesity among pre-school age internally displaced children and the associated risk factors. Materials and Methods: A cross-sectional study was conducted among 1,179 randomly selected children aged 6-59 months living in four internally displaced persons (IDPs) settlements of Abuja Municipal Area Council (AMAC), Federal Capital Territory (FCT), Nigeria. Weight and height measurements were taken, and a structured interviewer-administered questionnaire was used to collect data on the research variables. Data were analyzed using IBM SPSS version 25 computer statistical software package. Results: The prevalence of underweight was 18.9%, while overweight/obesity was 3.1%. The predictors of underweight were low birth weight (aOR = 2.67; 95% CI = 1.67 – 4.29), recent diarrhoea (aOR = 2.13; 95% = 1.02 – 4.44), and the child not eating from his/her own plate (aOR = 1.51; 95% CI = 1.04 – 2.19); while urban residence (aOR = 2.81; 95% CI = 1.16 – 6.78) and frequent ingestion of non-nutritious foods (aOR = 2.42; 95% CI = 1.21 – 4.85) were the determinants of overweight and obesity. Conclusions: A double burden of malnutrition exists among the IDPs in this study. Risk factors were demonstrable of household food insecurity and poor feeding practices, thus portending a cycle of morbidity and mortality among this vulnerable population and an urgent need for government to institute interventions for their prevention and control.