BACKGROUND: There is little research on alcohol and other drugs (AOD) use by school-age children in low-resource settings like Uganda. Including the voices of children in research can inform prevention and early intervention efforts for those at risk of AOD use. The aim of this study was to understand the perspectives of children aged 6 to 13 years regarding AOD in Uganda. METHODS: This qualitative study was conducted in Mbale district, Uganda from February to March 2020. Eight focus group discussions (FGDs) were conducted with 56 primary school-age children, stratified by age (6-9 and 10-13 years), sex (male and female), and school status (in school and out of school). All FGDs were conducted in either Lumasaaba or Luganda. The FGDs were audio-recorded, transcribed verbatim, and translated into English. Data were coded, and overarching themes were identified using thematic framework analysis. RESULTS: Two themes identified were (1) Children's perceptions and experiences with AODs. The participants understood alcohol by its consistency, colour, odour, and by brand/logo. They described the types and quantities of AOD consumed by school-age children, brewing processes for homemade alcoholic drinks, and short and long-term consequences of the use of alcohol. (2) Contributing factors to childhood drinking included: Stress relief for children who experienced multiple adversities (orphaned, poverty-stricken, and hailing from broken homes), fitting in with friends, influence from families, and media exposure that made alcohol look cool. Children would start drinking at an early age) or were given alcohol by their parents, sometimes before they could start talking. In the community, alcohol and other drugs were cheap and available and children could drink from anywhere, including in the classroom. CONCLUSIONS: Children eligible for primary education in Uganda can easily access and use AOD. Several factors were identified as contributing to alcohol and other drug use among children, including availability and accessibility, advertising, lack of parental awareness and supervision, peer influence, adverse childhood experiences, socioeconomic factors, and cultural norms. There is a need for multi-sectoral action for awareness of childhood AOD use and deliberate consideration of children in the planning, design, and implementation of research, policies, and programs for prevention and early intervention.