Objective In this study, we aimed to investigate self-esteem and clinical features in clinically referred children and adolescents with attention-deficit/hyperactivity disorder (ADHD) and comorbid Social Anxiety Disorder (SAD) and compare these to children and adolescents without SAD. Methods One hundred and twenty child and adolescent drug-naïve outpatients (6–15 years of age) with a primary diagnosis of ADHD were included. Schedule for Affective Disorders and Schizophrenia for School Age Children–Present and Lifetime Version (K-SADS-PL), was used to evaluate ADHD and comorbidities. Parents filled in clinical and sociodemographic data form, Conners Parent Rating Scale (CPRS) and patients filled in Rosenberg Self-esteem Scale (RSES) and Çapa Social Phobia Scale for children and adolescents (ÇESFÖ). Results Forty-six of the 120 (38.3%) children had comorbid SAD. Forty-six patients with SAD (ADHD + SAD group) and 74 patients without SAD (ADHD without SAD group) were compared in terms of the sociodemographic and clinical features, rate of psychiatric comorbidities, and rating scale scores. The rate of inattentive subtype of ADHD (p = 0.009), and social anxiety symptom scores (p < 0.001) were higher and self-esteem was lower (p < 0.001) in the ADHD + SAD group. Additionally, there was a statistically significant correlation between ÇESFÖ scores and CPRS anxiety subscale scores (r = 0.300, p = 0.001), and also Rosenberg self-esteem scale scores (r = 0.470, p < 0.001). Conclusion Children and adolescents with ADHD who had comorbid SAD may differ from ADHD patients without SAD in terms of ADHD subtype, clinical features and self-esteem.