Background: There is concern about radiation dose in children during cardiovascular catheterization and many believe that theuse of computerized tomography is much better than conventional catheterization and angiography. The aim of this study is tocompare the radiation dose between diagnostic and therapeutic procedures in children. Methods: 178 patients with congenital heart disease enrolled in this study. Patients have been divided into 3 groups of CT angiography, conventional angiography and intervention. Data include: sex, age, weight, fluoroscopy time, total radiation dose of CT angiography, the amount of reference point air Kerma (Ka, r) (reference dose) and kerma area product (Pka) of fluoroscopy machine. Peak skin dose (PSD) was calculated for intervention and conventional angiography patients using the following formula: PSD = 249+ 5. 2 PKA. The data has been analyzed by SPSS version 20. In this study the P-value less than 0. 05 was considered meaningful. Results: The patients were similar in sex, age and weight in all the three groups. The mean reference point air kerma (ka, r) inintervention group was meaningfully higher than the other two groups (P < 0. 001), but in some patients of CT Angiography groupthe radiation dose was higher than conventional angiography group. The mean kerma area product (pka) in intervention group was higher than angiography group, although this difference is lessmeaningful statistically (P = 0. 049). The Fluoroscopy time (P = 0. 035) in intervention group was meaningfully higher than angiographygroup. The mean calculated pick skin dose (PSD) was 437 383 miligray and 213 508 miligray for intervention and conventionalangiography groups respectively (P < 0. 001). In intervention group, Fluoroscopy time (P = 0. 037), ka, r (P = 0. 17) ( and Pka (P =0. 02) are more about VSD closure than other procedures. Conclusions: Given the results of this study, the use of fluoroscopy for diagnosis and treatment of pediatric cardiovascular diseasesis safe but with due attention to sensitivity of children to some side effects of X-ray compared to adults, considering safety advicesin order to reduce fluoroscopy time, radiation dose and the use of standard protection to reduce X-ray absorption is necessary.