Objective: The purpose of this study was to compare the effects of ketamine-midazolam and remifentanil-midazolam combinations on hemodynamic, sedation and recovery levels in pediatric cardiac catheterization patients who received anesthesia. Material and Methods: One hundred ASA II-III pediatric patients between ages of 3 months and 10 years, scheduled for cardiac catheterization between June 2011 and August 2011 were randomly allocated into 2 equal (n=50) study groups assigned to receive sedation with ketamine (1 mgkg-1) (Group I) or remifentanil (0.1 mgkg-1min -1) infusions (Group II). Patients requiring mechanical ventilation and intravenous inotropic support were excluded from the study analysis. Before induction of anesthesia, patients were transferred to the cardiac catheterization laboratory and their electrocardiograms (ECG) and oxygen saturation (SpO2) levels were continuously measured. Before premedication, all patients were monitored and their blood pressures (NIBP) were measured with an noninvasive method, and sedation scores according to Modified Ramsey Sedation Scale (MRSS). recorded Both groups initially received midazolam 0.05-0.1 mgkg-1 for premedication. After catheterization anaesthetic medications of the patients were stopped, and they were sent to recovery room where their hemodynamic data and recovery scores were recorded. Results: Both groups demonstrated similar demographic characteristics. However, Patients received remifentanil-midazolam infusion reported significantly lower heart rate and mean blood pressure values compared to patients who received ketamine-midazolam. Hypotension with bradycardia were observed in these patients. There was no significant difference between the two groups in terms of MRS scores, duration of anesthesia ve process time. However, the recovery time of the patients in Group I was significantly longer than Group II. Conclusion: In this study, we have concluded that the infusion of remifentanil-midazolam combination provides a satisfactory sedation, and shorter recovery time as an alternative to ketamine used routinely in pediatric cardiac catheterization.