Objective: In this study, we aimed to determine the diagnostic and clinical predictive value of optic nerve sheath diameter (ONSD) measurement in pediatric patients suspected of increased intracranial pressure (IICP) by comparing sonographic ONSD values with radiological parameters and controls. Materials and Methods: In total, 57 pediatric patients with suspected IICP who underwent computed tomography (CT) scans were included in this prospective, observational study; meanwhile, 35 patients were included as controls. Measurements were obtained while the patients were in supine position with their eyes closed, and transbulbar images of both eyes were obtained via a 6–15 MHz linear probe. The CT scans were assessed by a radiologist blinded to sonographic measurements. Glasgow coma scale of patients, service where they were followed, clinical results, CT, and ONSD values were assessed in this study. Results: In the patient group, 26 of the patients were girls (35.4%), and the mean age was 138±56 months (min-max: 82–194 months). Meanwhile, in the control group, 18 of the patients were girls (40.9%), and mean age was 151±45 months (min-max: 106–196 months). As per our findings, 31 patients (54.4%) presented with high-energy trauma. Mean ONSD was 0.5±0.07 cm in the patient group, whereas it was 0.3±0.02 cm in the control group (p=0.008). It was 0.55±0.07 cm in patients with cerebral edema (CE) on CT scan (p=0.013). Based on the presence of CE as detected via CT scan, cut-off value for measurement was determined to be 0.49 cm, with 83.33% sensitivity and 68.42% specificity (AUC: 0.784). Conclusion: Optic nerve sheath measurement can be utilized to immediately support diagnosis and predict follow-up in the assessment of pediatric patients with ICP elevation.