Purpose: The purpose of this study is to identify the effects of a standardized educational program to improve nursing competency on newly graduated nurses in a children's hospital after developing and applying a pediatric nurse education program. The effectiveness of the program was confirmed by evaluating the clinical competency and field adaptation.Methods: In the first step, an education program was developed using the analysis, design, development, implementation and evaluation (ADDIE) model. As a second step, a similar experimental study of a single group repeat measures design was conducted to evaluate the clinical competency and field adaptation over time after application of the program. Additionally, a focus group interviews were conducted to collect subjective data on the effects and improvement points of the program.Results: As a result of applying the program, there was a significant change in the clinical competence and the field adaptation of newly graduated nurses in a children’s hospital. The categories derived from the focus group interviews were “getting special guidance,” “better care,” “becoming a nurse at a children's hospital” and “winning together.”Conclusion: It was confirmed that the education program enhances the clinical competency of new nurses in children's hospitals. In addition, it provided the necessary data to understand the experiences of new nurses, help them adapt effectively, and establish appropriate interventions.