Background: Diarrhoea is a major public health concern in the North-eastern region of India. The present study aims to find out the district-wise prevalence of diarrhoea among the children of under 5 years of age of the state of Assam, using nationally representative NHFS-4 data. The study also focuses on examining some of the contextual factors affecting the occurrence. Material and methods: The data used in this study is from the fourth series of National Family Health Survey (NFHS-4) 2015-16. A total of 10309 samples of children under 5 years of age were used for this study. Data was arranged, analysed and presented with the help of IBM SPSS version 26.0 and MS Excel 2021 version. BACKWARD stepwise logistic regression analysis model was used for determining predictability of variance all the variables in occurrence of diarrhoea among the children. Results: It is evident that ten district are showing higher prevalence of diarrhoea than the state average. The prevalence diarrhoea was found to be significantly higher among the tribals. It is also significantly higher among the younger age groups. Religion was the strongest predictor of diarrhoea among the children under 5.