Background: Despite the scaling-up of Insecticidal Treated Nets (ITNs) distribution in Ethiopia, its use among net owning households has not been satisfactory. Hence, in addition to scaling up of net distribution, periodic assessment of the use and barriers against the use of bed nets among high risk population is necessary. Objective: The objective of this study was to assess the ITNs use and its barriers among under-five children in Adami Tullu District, Ethiopia. Methodology: A small-scale qualitative approach was used. Purposive sampling was employed to get mothers with under-five children in all kebeles. Semi-structured discussion guide was used for focus group discussions which was conducted in Afaan Oromo (local language of the study area). Open code computer program was used for the analysis of the data. The data was coded; categorized and appropriate themes were developed. The data was summarized and presented along the main themes.