Background – Attention deficit and hyperactivity disorder (ADHD) prevalence is increasing, compliance to treatment is often poor, and additional treatment options are warranted. We aim to investigate whether individualized homeopathic treatment is effective in children with ADHD when compared to placebo or usual care alone. Methods – Thirty-seven online sources were searched with a last update in March 2021. Studies investigating the effects of individualized homeopathy against any control in ADHD (ICD-10 category F90.0) were eligible. Data were extracted to a predefined excel sheet independently by two reviewers. Results – Six studies were analyzed. All but one were randomized and showed low-to-moderate risk of bias; two were controlled against standard treatment and four were placebo-controlled and double-blinded. The meta-analysis revealed a significant effect size across studies of Hedges’ g = 0.542 (95% CI 0.311–0.772; z = 4,61; p < 0.001) against any control and of g = 0.605 (95% CI 0.05–1.16; z = 2.16, p = 0.03) against placebo (n = 4). The effect estimations are based on studies with an average sample size of 52 participants. Conclusions – Individualized homeopathy showed a clinically relevant and statistically robust effect in the treatment of ADHD.