Background: Attention-deficit/hyperactivity disorder is among the common neuropsychiatric disorder affecting children and adolescents. The disease affects their life, parents, and community when left untreated. Although evidence indicated a high prevalence of attention-deficit/hyperactivity disorder in the developed world, there is limited evidence in developing countries, particularly, Ethiopia. therefore, this study aimed to determine the prevalence and associated factors of attention deficit hyperactivity disorder among children aged 6 to 17 years in Jimma town.Methods: A community-based cross-sectional study was conducted from August to September 2021 among children aged 6 to 17 years in Jimma town. A multistage sampling technique was applied to select 520 study participantsts. Data were collected using a structured, pretested, and a face-to-face interview. Vanderbilt's attention-deficit hyperactivity disorder rating scale with parent rating was used. The association between independent variables and the outcome variable was investigated using bi-variable and multivariable logistic regression. On the final model level of significance was set at a p-value of <0.05.Result: A total of 504 participants were involved in the study with a response rate of 96.9%.The overall prevalence of attention deficit hyperactivity disorder in this study was (9.9%, n=50). Maternal complication during pregnancy (Adjusted odds ratio (AOR) = 3.56, 95% CI (1.44-8.79)), mothers illiteracy (AOR=3.10, 95% CI (1.24-7.79)), being primary school (AOR= 2.97, 95% CI (1.32-6.73)), history of head trauma (AOR= 3.20, 95% CI (1.25-8.16)), maternal alcohol use during pregnancy (AOR= 3.54, 95% CI (1.26-10))), bottle feeding during first six months (AOR=2.87, 95% (1.20-6.93)) and child’s age 6-11 years (AOR=3.86, 95% CI (1.77-8.43)) were significantly associated with attention deficit hyperactivity disorder. Conclusion: In this study, 1 in 10 children and adolescents in Jimma town had attention deficit hyperactivity disorder. Therefore, the prevalence of attention deficit hyperactivity disorder was high. Early detection and management of maternal complications are important to reduce the prevalence of attention deficit hyperactivity disorder among children. Finally, mental health professionals should be sensitized to thoroughly explore treatment options, as well as their advantages and risks.