Objective: We aimed to investigate the effects of dexmedetomidine premedication before intravenous infusion of ketamine in agitated children undergoing strabismus surgery. Subjects and Methods: We enrolled 60 agitated pediatric patients, aged 4.5–11 years. The patients were randomly allocated to one of two anesthesia regimens. Group D patients were premedicated with a single dose of intravenous dexmedetomidine 0.5 µg/kg whereas group P patients received a placebo. Patients in both groups were administered intravenous ketamine 1 mg/kg i.v. over 1 min followed by a continuous infusion of ketamine 1–3 mg/kg/h i.v. (n = 30). Patients were intubated after receiving fentanyl 1 µg/kg and rocuronium bromide 0.5 mg/kg. Results: 21 (70%) patients in group D did not show the oculocardiac reflex (OCR) versus 7 (23%) in group P (p = 0.0006). The preoperative and postoperative agitation scores (p = 0.0001 and p = 0.03, respectively), the score on the Faces Pain Scale during awakening [3.0 (interquartile range, IQR 2.0–4.0) in group D and 0.0 (IQR 1.0–2.25) in group P] (p = 0.001) and at the 60th postoperative minute [IQR 2.0 (1.5–3.0) in group D and 2.0 (IQR 1.5–3.0) in group P] (p = 0.004), sore throat (26.6% in group D and 60% in group P) (p = 0.01) and analgesic requirement (20% in group D and 53% in group P) (p = 0.01) in group P were significantly higher than in group D. The Ramsay Sedation Score (RSS) in group D was significantly higher than in group P during awakening [2.0 (2.0–2.0) in group D and 4.5 (4.0–5.0) in group P] (p = 0.0001). Conclusion: Dexmedetomidine premedication followed by intravenous infusion of ketamine was effective in decreasing OCR, agitation, pain, analgesic requirement in agitated children undergoing strabismus surgery.