Objective: Biological processes are the sum of metabolic reactions that result in intermediate and end metabolite products. These processes are the reflection of genetic regulation and are profoundly impacted by environmental influence and changes, including those associated with attention-deficit/hyperactivity disorder (ADHD). This study aimed to assess the untargeted plasma metabolomic profile of children and adolescents with ADHD and to compare them with healthy controls and to study associations of dysregulated metabolic parameters with the clinical and socio-demographic parameters of ADHD. Methods: This study involved 42 registered cases of ADHD among children aged 6 to 16 years, diagnosed based on DSM-5 criteria. Each case was matched by age and gender with 24 healthy controls. The severity of ADHD was evaluated using the ADHD Rating Scale, while behavioral issues were assessed through the Child Behavior Checklist. The gas chromatography-mass spectrometry technique was employed to examine changes in plasma metabolite content. Results: We identified a total of 45 metabolites in the ADHD subtypes, which exhibited altered levels compared to the control group. The content of these metabolites and associated metabolic pathways showed significant differences between ADHD subjects and controls. Furthermore, we analyzed biomarkers derived from the compounds with the greatest fold changes in accumulation levels. Conclusion The identification and analysis of these metabolites and metabolic pathways represent a promising new approach for tracking disease progression in ADHD. The findings of this study indicate that metabolite-based biomarkers may hold considerable potential for effective disease management.